Catholytes for solid state rechargeable batteries, battery architectures suitable for use with these catholytes, and methods of making and using the same

ABSTRACT

Provided herein are electrochemical cells having a solid separator, a lithium metal anode, and a positive electrode catholyte wherein the electrochemical cell includes a nitrile, dinitrile, or organic sulfur-including solvent and a lithium salt dissolved therein. Also set forth arc methods of making and using these electrochemical cells.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 62/380,942, filed Aug. 29, 2016, the entire content of which isherein incorporated by reference in its entirety for purposes.

FIELD

The present disclosure sets forth high voltage-stable electrolytes, suchas dinitrile solvents and mixtures of dinitrile solvents and nitrilesolvents, and organic sulfur-including solvents which include lithiumsalts, electrochemical cells and devices which include theseelectrolytes, and methods of making and using the same.

BACKGROUND

Conventional lithium rechargeable batteries use a porous polyolefinseparator which is soaked with liquid electrolytes. This separatorelectrically insulates the positive and negative electrodes of thebattery but remains conductive towards Li⁺ ions. This conventionalbattery architecture relies on carbonate-based organic solvents, whichsuffer from flammability and leakage problems, to achieve commerciallyrelevant ion-conductivity, cycle life, and shelf life metrics.Carbonates also have a limited (i.e., narrow) voltage stability windowand are particularly unstable when stored at high voltages. Mostimportantly, carbonate solvents are not chemically compatible with alllithium metal negative electrodes.

Some researchers have attempted to use nitrile solvents in place ofcarbonate solvents. See, for example, Abu-Lebdeh, Y., et al., Journal ofPower Sources 189 (2009) 576-579; Abu-Lebdeh, Y., et al., Journal of TheElectrochemical Society, 156 (1) A60-A65 (2009); Long, S. et al., SolidState Ionics 161 (2003) 105— 112; Geirhos, K. et al., The Journal ofChemical Physics, 143, 081101 (2015) ; Zachariah, M., et al. J. Phys.Chem. C 2015, 119, 27298-27306; and Alarco, P-J., et al., naturematerials (3), July, 2004. However, these prior uses of nitrile solventssuffered from instability with low voltage anodes such as graphite orlithium metal which are used in high energy batteries. This was due inpart because nitrile solvents are not able to form a passivatingsolid-electrolyte-interface (SEI) on low voltage anodes, such as lithiummetal. To date, nitrile solvents have not, which makes nitrile solventsunusable in high energy (i.e., high voltage) batteries. As a result,these graphite and lithium metal anodes typically have, prior to theinstant disclosure, required a carbonate co-solvent for the electrolyte.

Some researchers have electrospun or polymerized nitrile-based materialsfor battery applications, for example Zhou D., et al. (2015) In SituSynthesis of a Hierarchical All-Solid-State Electrolyte Based on NitrileMaterials for High-Performance Lithium Ion Batteries. Adv. EnergyMater., 5: 1500353. doi: 10.1002/aenm.201500353. However, the impedanceobserved in these electrospun or polymerized nitrile-based materialshigh, the low temperature power capability of the batteries which usedthese electrospun or polymerized nitrile-based materials is poor, andthe electrospun or polymerized nitrile-based materials could not blockthe formation of lithium dendrites at commercially relevant currentdensities and commercially relevant throughput amounts of of lithiumduring electrochemical cycling.

Accordingly, there exists a need for improved electrolytes forrechargeable batteries. Set forth herein are such improved electrolytesas well as other solutions to problems in the relevant field.

SUMMARY

In one embodiment, set forth herein is an electrochemical cell whichincludes:

a lithium metal negative electrode;

a solid separator; and

a positive electrode,

wherein the positive electrode includes an active material and acatholyte, wherein the catholyte includes a catholyte solvent and alithium salt, wherein the catholyte solvent comprises a nitrile solvent,a dinitrile solvent, an organic sulfur-including solvent, or acombination thereof

In a second embodiment, set forth herein is a catholyte including anitrile solvent and a lithium salt,

-   -   wherein the nitrile solvent is selected from acetonitrile,        butyronitrile, benzonitrile, glutaronitrile, hexanenitrile,        fluoroacetonitrile, nitroacetonitrile, malononitrile,        ethoxyacetonitrile, methoxyacetonitrile, pentanenitrile,        propanenitrile, succinonitrile, adiponitrile, and        iso-butyronitrile;    -   wherein the lithium salt is selected from LiPF₆, LiBOB, LiTFSi,        LiBF₄, LiClO₄, LiAsF₆, LiFSI, LiClO₄, LiI, and a combination        thereof; and    -   wherein the catholyte is chemically compatible with a solid        separator set forth herein.

In a third embodiment, set forth herein is a catholyte comprising anorganic sulfur-including solvent, optionally a co-solvent, and a lithiumsalt,

-   -   wherein the organic sulfur-including solvent is selected from        ethyl methyl sulfone, dimethyl sulfone, sulfolane, allyl methyl        sulfone, butadiene sulfone, butyl sulfone, methyl        methanesulfonate, dimethyl sulfite, wherein the co-solvent is a        carbonate solvent;    -   wherein the lithium salt is selected from LiPF₆, LiBOB, LiTFSi,        LiBF₄, LiClO₄, LiAsF₆, LiFSI, LiClO₄, LiI, and a combination        thereof.

In a fourth embodiment, set forth herein is a method of using anelectrochemical cell set forth herein, comprising charging theelectrochemical cell to a voltage greater than 4.3V.

In a fifth embodiment, set forth herein is a method of storing anelectrochemical cell, including providing an electrochemical cell setforth herein, wherein the electrochemical cell has greater than 20%state-of-charge (SOC); and storing the battery for at least one day.

In a sixth embodiment, set forth herein is a method for making acatholyte set forth herein which includes a nitrile solvent and alithium salt, wherein the method includes providing a nitrile solvent,providing a lithium salt, mixing the nitrile solvent and the lithiumsalt to form a mixture, and optionally heating the mixture.

In a seventh embodiment, set forth herein is a method for making acatholyte set forth herein which includes an organic sulfur-includingsolvent and a lithium salt, wherein the method includes providing anorganic sulfur-including solvent, providing a lithium salt, mixing theorganic sulfur-including solvent and the lithium salt to form a mixture,and optionally heating the mixture.

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIG. 1 shows a schematic of an example of an electrochemical cell havinga catholyte in the positive electrode space which includes a dinitrilesolvent

FIG. 2 shows a plot of the median charge ASR-DC (Ω-cm²) for twoelectrochemical cells, after storage at 4.6 V, and wherein oneelectrochemical cell includes a catholyte including succinonitrile (SCN)at 12 mol % LiBF₄ and wherein the other electrochemical cell includes acatholyte including EC:EMC+1 M LiPF6+2 wt % monofluoroethylene carbonate(FEC). In the figure, circles refer to succinonitrile+12 mol % LiBF₄,and triangles refer to EC:EMC+1 M LiPF6+2 wt % FEC. Elyte in FIG. 2refers to electrolyte. EC refers to ethyl carbonate solvent. EMC refersto ethyl methyl carbonate solvent.

FIG. 3 shows a plot of the median discharge ASR-DC (Ω-cm²) for twoelectrochemical cells, after storage at 4.6 V, and wherein oneelectrochemical cell includes a catholyte including succinonitrile (SCN)at 12 mol % LiBF4 and wherein the other electrochemical cell includes acatholyte including EC:EMC+1 M LiPF6+2 wt % monofluoroethylene carbonate(FEC). In the figure, circles refer to succinonitrile+12 mol % LiBF₄,and triangles refer to EC:EMC+1 M LiPF6+2 wt % FEC.

FIG. 4 shows a plot of active mass-specific discharge capacity (mAh/g)as a function of cycle index for devices made according to Example 2with two different catholytes.

FIG. 5 shows a plot of the median charge and discharge ASRdc (Ω-cm²) fortwo electrochemical cells, both stored at 4.6 V, and wherein oneelectrochemical cell includes a catholyte including succinonitrile at 12mol % LiBF₄ and wherein the other electrochemical cell includes acatholyte including EC:EMC+1 M LiPF6+2 wt % FEC. In the figure, circlesrefer to succinonitrile+12 mol % LiBF4, and triangles refer to EC:EMC at3.7 w/w+1 M LiPF6+2 wt % FEC.

FIG. 6 shows a plot of mass percent of Gel Polymer Soaked in Electrolytefor two electrochemical cells, wherein one electrochemical cell includesa catholyte including adiponitrile and 1M LiTFSi and wherein the otherelectrochemical cell includes a catholyte including EC:EMC+1 M LiPF6+2wt % FEC. In the figure, solid line is adiponitrile+1 M LiTFSi, and thedoted line is EC:EMC+1 M LiPF6+2 wt % FEC.

FIG. 7 shows a plot of charge ASR growth wherein the cell is preparedwith sulfolane and ethylene carbonate (3:7 v/v)+2M LiPF₆ vs ethyl-methylcarbonate, ethylene carbonate (3:7v/v)+1M LiPF6 for 10 cycles, C/3pulses, from 2.7-4.2 V at 45° C. The cathode is NMC, and the separatoris solid-state separator material. Solid line is EC:EMC 3:7 v/v+1MLiPF₆; dotted line is EC:Sulfolane 3:7 v/v+2 M LiPF₆.

FIG. 8 shows a plot of discharge and charge ASR versus cycle life for500 cycles for a cell.

DETAILED DESCRIPTION A. DEFINITIONS

As used herein, the term “about,” when qualifying a number, e.g., about15% w/w, refers to the number qualified and optionally the numbersincluded in a range about that qualified number that includes ±10% ofthe number. For example, about 15% w/w includes 15% w/w as well as 13.5%w/w, 14% w/w, 14.5% w/w, 15.5% w/w, 16% w/w, or 16.5% w/w. For example,“about 75° C,” includes 75° C. as well 68° C., 69° C., 70° C., 71° C.,72° C., 73° C., 74° C., 75° C., 76° C., 77° C., ° C., 79° C., 80° C., °C., ° C., or 83° C.

As used herein, the phrase “Li⁺ ion-conducting separator” refers to anelectrolyte which conducts Li⁺ ions, is substantially insulating toelectrons (e.g., the lithium ion conductivity is at least 10³ times, andoften 10⁶ times, greater than the electron conductivity), and which actsas a physical barrier or spacer between the positive and negativeelectrodes in an electrochemical cell.

As used herein, the phrases “solid separator,” “solid electrolyte,”“solid-state separator,” and “solid-state electrolyte” refer to Li⁺ion-conducting separators that are solids at room temperature andinclude at least 50 vol % ceramic material.

As used herein, “selected from the group consisting of” refers to asingle member from the group, more than one member from the group, or acombination of members from the group. A member selected from the groupconsisting of A, B, and C includes, for example, A only, B only, or Conly, as well as A and B, A and C, B and C, as well as A, B, and C.

As used herein, the phrase “electrochemical cell” refers to, forexample, a “battery cell” and includes a positive electrode, a negativeelectrode, and an electrolyte therebetween which conducts ions (e.g.,Li⁺) but electrically insulates the positive and negative electrodes. Insome embodiments, a battery may include multiple positive electrodesand/or multiple negative electrodes enclosed in one container.

As used herein the phrase “electrochemical stack” refers to one or moreunits which each include at least a negative electrode (e.g., Li, LiC₆),a positive electrode (e.g., Li-nickel-manganese-oxide or FeF3,optionally combined with a solid-state electrolyte or a gelelectrolyte), and a solid electrolyte (e.g., an oxide electrolyte setforth herein, a lithium-stuffed garnet film, or a lithium-stuffed garnetpellet) between and in contact with the positive and negativeelectrodes. In some examples, between the solid electrolyte and thepositive electrode, there is an additional layer comprising a compliant(e.g., gel electrolyte). An electrochemical stack may include one ofthese aforementioned units. An electrochemical stack may include severalof these aforementioned units arranged in electrical communication(e.g., serial or parallel electrical connection). In some examples, whenthe electrochemical stack includes several units, the units are layeredor laminated together in a column. In some examples, when theelectrochemical stack includes several units, the units are layered orlaminated together in an array. In some examples, when theelectrochemical stack includes several units, the stacks are arrangedsuch that one negative electrode is shared with two or more positiveelectrodes. Alternatively, in some examples, when the electrochemicalstack includes several units, the stacks are arranged such that onepositive electrode is shared with two or more negative electrodes.Unless specified otherwise, an electrochemical stack includes onepositive electrode, one solid electrolyte, and one negative electrode,and optionally includes a gel electrolyte layer between the positiveelectrode and the solid electrolyte. In some examples, the gelelectrolyte layer is also included in the positive electrode. In someexamples, the gel electrolyte includes any electrolyte set forth herein,including a nitrile, dinitrile, organic sulfur-including solvent, orcombination thereof set forth herein.

As used herein, the term “electrolyte” refers to a material that allowsions, e.g., Li⁺, to migrate or conduct therethrough but which does notallow electrons to conduct therethrough. Electrolytes are useful forelectrically isolating the cathode and anodes of a secondary batterywhile allowing ions, e.g., Li⁺, to transmit through the electrolyte.Solid electrolytes, in particular, rely on ion hopping through rigidstructures. Solid electrolytes may be also referred to as fast ionconductors or super-ionic conductors. Solid electrolytes may be alsoused for electrically insulating the positive and negative electrodes ofa cell while allowing for the conduction of ions, e.g., Li⁺, through theelectrolyte. In this case, a solid electrolyte layer may be alsoreferred to as a solid electrolyte separator or solid-state electrolytesepatator.

As used herein, the phrases “gel electrolyte” unless specifiedotherwise, refers to a suitable Li⁺ ion conducting gel or liquid-basedelectrolyte, for example, those set forth in U.S. Pat. No. 5,296,318,entitled RECHARGEABLE LITHIUM INTERCALATION BATTERY WITH HYBRIDPOLYMERIC ELECTROLYTE. A gel electrolyte has a lithium ion conductivityof greater than 10⁻⁵ S/cm at room temperature, a lithium transferencenumber between 0.05-0.95, and a storage modulus greater than the lossmodulus at some temperature. A gel electrolyte may comprise a polymermatrix, a solvent that gels the polymer, and a lithium containing saltthat is at least partly dissociated into Li⁺ ions and anions.Alternately, a gel electrolyte may comprise a porous polymer matrix, asolvent that fills the pores, and a lithium containing salt that is atleast partly dissociated into Li⁺ ions and anions where the pores haveone length scale less than 10 μm.

As used herein, the term “laminating” refers to the process ofsequentially depositing a layer of one precursor specie, e.g., a lithiumprecursor specie, onto a deposition substrate and then subsequentlydepositing an additional layer onto an already deposited layer using asecond precursor specie, e.g., a transition metal precursor specie. Thislaminating process can be repeated to build up several layers ofdeposited vapor phases. As used herein, the term “laminating” alsorefers to the process whereby a layer comprising an electrode, e.g.,positive electrode or cathode active material comprising layer, iscontacted to a layer comprising another material, e.g., garnetelectrolyte. The term “laminating” also refers to the process whereby atleast two layers comprising a solid electrolyte material are contactedtogether. The laminating process may include a reaction or use of abinder which adheres of physically maintains the contact between thelayers which are laminated. The process of laminating one layer toanother layer results in one layer being laminated to the other layer.

As used herein, the phrase “directly contacts” refers to thejuxtaposition of two materials such that the two materials contact eachother sufficiently to conduct either an ion or electron current. As usedherein, direct contact refers to two materials in contact with eachother and which do not have any materials positioned between the twomaterials which are in direct contact.

As used herein, the terms “cathode” and “anode” refer to the electrodesof a battery. The cathode and anode are often referred to in therelevant field as the positive electrode and negative electrode,respectively. During a charge cycle in a Li-secondary battery, Li ionsleave the cathode and move through an electrolyte, to the anode. Duringa charge cycle, electrons leave the cathode and move through an externalcircuit to the anode. During a discharge cycle in a Li-secondarybattery, Li ions migrate towards the cathode through an electrolyte andfrom the anode. During a discharge cycle, electrons leave the anode andmove through an external circuit to the cathode.

As used herein, the phrase “positive electrode” refers to the electrodein a secondary battery towards which positive ions, e.g., Li⁺, conduct,flow or move during discharge of the battery. As used herein, the phrase“negative electrode” refers to the electrode in a secondary battery fromwhere positive ions, e.g., Li⁺, flow or move during discharge of thebattery. In a battery comprised of a Li-metal electrode and a conversionchemistry, intercalation chemistry, or combinationconversion/intercalation chemistry-including electrode (i.e., cathodeactive material; e.g., NiF_(x), NCA, LiNi_(x)Mn_(y)Co₂O₂ [NMC] orLiNi_(x)Al_(y)Co_(z)O₂ [NCA], wherein x+y+z=1), the electrode having theconversion chemistry, intercalation chemistry, or combinationconversion/intercalation chemistry material is referred to as thepositive electrode. In some common usages, cathode is used in place ofpositive electrode, and anode is used in place of negative electrode.When a Li-secondary battery is charged, Li ions move from the positiveelectrode (e.g., NiF_(x), NMC, NCA) towards the negative electrode(e.g., Li-metal). When a Li-secondary battery is discharged, Li ionsmove towards the positive electrode and from the negative electrode.

As used herein, the term “catholyte” refers to a Li ion conductor thatis intimately mixed with, or that surrounds and contacts, or thatcontacts the positive electrode active materials and provides an ionicpathway for Li⁺ to and from the active materials. Catholytes suitablewith the embodiments described herein include, but are not limited to,catholytes having the acronyms name LPS, LXPS, LXPSO, where X is Si, Ge,Sn, As, Al, LATS, or also Li-stuffed garnets, or combinations thereof,and the like. Catholytes may also be liquid, gel, semi-liquid,semi-solid, polymer, and/or solid polymer ion conductors known in theart. In some examples, the catholyte includes a gel set forth herein. Insome examples, the gel electrolyte includes any electrolyte set forthherein, including a nitrile, dinitrile, organic sulfur-includingsolvent, or combination thereof set forth herein.

In some examples, the electrolytes herein may include, or be layeredwith, or be laminated to, or contact a sulfide electrolyte. As usedhere, the phrase “sulfide electrolyte,” includes, but is not limited to,electrolytes referred to herein as LSS, LTS, LXPS, or LXPSO, where X isSi, Ge, Sn, As, Al, LATS. In these acronyms (LSS, LTS, LXPS, or LXPSO),S refers to the element S, Si, or combinations thereof, and T refers tothe element Sn. “Sulfide electrolyte” may also includeLi_(a)P_(b)S_(c)X_(d), Li_(a)B_(b)S_(c)X_(d), Li_(a)Sn_(b)S_(c)X_(d) orLi_(a)Si_(b)S_(c)X_(d) where X═F, Cl, Br, I, and 10%≤a≤50%, 10%≤b≤44%,24%≤c≤70%, 0≤d≤18% and may further include oxygen in small amounts. Forexample, oxygen may be present as a dopant or in an amount less than 10percent by weight. For example, oxygen may be present as a dopant or inan amount less than 5 percent by weight.

As used herein, the phrase “sulfide based electrolytes” refers toelectrolytes that include inorganic materials containing S which conductions (e.g., Li⁺) and which are suitable for electrically insulating thepositive and negative electrodes of an electrochemical cell (e.g.,secondary battery). Exemplary sulfide based electrolytes include, butare not limited to, those electrolytes set forth in International PatentApplication PCT Patent Application No. PCT/US14/38283, SOLID STATECATHOLYTE OR ELECTROLYTE FOR BATTERY USING LiAMPBSc (M=SI, GE, AND/ORSN), filed May 15, 2014, and published as WO 2014/186634, on Nov. 20,2014, which is incorporated by reference herein in its entirety; also,U.S. Pat. No. 8,697,292 to Kanno, et al , the contents of which areincorporated by reference in their entirety.

As used here, the phrase “sulfide electrolyte” includes, but are notlimited to, LSS, LTS, LXPS, LXPSO, where X is Si, Ge, Sn, As, Al, LATS,also Li-stuffed garnets, or combinations thereof, and the like, S is S,Si, or combinations thereof, T is Sn.

As used herein, “SLOPS” includes, unless otherwise specified, a 60:40molar ratio of Li₂S:SiS₂ with 0.1-10 mol. % Li₃PO₄. In some examples,“SLOPS” includes Li₁₀Si₄Si₃ (50:50 Li₂S:SiS₂) with 0.1-10 mol. % Li₃PO₄.In some examples, “SLOPS” includes Li₂₆Si₇S₂₇ (65:35 Li₂S:SiS₂) with0.1-10 mol. % Li₃PO₄. In some examples, “SLOPS” includes Li₄SiS₄ (67:33Li₂S:SiS₂) with 0.1-5 mol. % Li₃PO₄. In some examples, “SLOPS” includesLi₁₄Si₃S₁₃ (70:30 Li₂S:SiS₂) with 0.1-5 mol. % Li₃PO₄. In some examples,“SLOPS” is characterized by the formula (1−x)(60:40Li₂S:SiS₂)*(x)(Li₃PO₄), wherein x is from 0.01 to 0.99. As used herein,“LBS-PDX” refers to an electrolyte composition ofLi₂S:B₂S_(3:)Li₃PO₄:LiX where X is a halogen (X═F, Cl, Br, I). Thecomposition can include Li₃BS₃ or Li₅B₇S₁₃ doped with 0-30% lithiumhalide such as LiI and/or 0-10% Li₃PO₄.

As used here, “LBS” refers to an electrolyte material characterized bythe formula LiaBbSc and may include oxygen and/or a lithium halide (LiF,LiCl, LiBr, LiI) at 0-40 mol %.

As used here, “LPSO” refers to an electrolyte material characterized bythe formula Li_(x)P_(y)S_(z)O_(w) where 0.33≤x≤0.67, 0.07≤y≤0.2,0.4≤z≤0.55, 0≤w≤0.15. Also, LPSO refers to LPS, as defined above, thatincludes an oxygen content of from 0.01 to 10 atomic %. In someexamples, the oxygen content is 1 atomic %. In other examples, theoxygen content is 2 atomic %. In some other examples, the oxygen contentis 3 atomic %. In some examples, the oxygen content is 4 atomic %. Inother examples, the oxygen content is 5 atomic %. In some otherexamples, the oxygen content is 6 atomic %. In some examples, the oxygencontent is 7 atomic %. In other examples, the oxygen content is 8 atomic%. In some other examples, the oxygen content is 9 atomic %. In someexamples, the oxygen content is 10 atomic %.

As used herein, the term “LBHI” or “LiBHI” refers to a lithiumconducting electrolyte comprising Li, B, H, and I. More generally, it isunderstood to include aLiBH₄+bLiX where X═Cl, Br, and/or I and wherea:b=7:1, 6:1, 5:1, 4:1, 3:1, 2:1, or within the range a/b=2-4. LBHI mayfurther include nitrogen in the form of aLiBH₄+bLiX+cLiNH₂ where(a+c)/b=2-4 and c/a=0-10.

As used herein, the term “LPSI” refers to a lithium conductingelectrolyte comprising Li, P, S, and I. More generally, it is understoodto include aLi₂S+bP₂S_(y)+cLiX where X═Cl, Br, and/or I and where y=3-5and where a/b=2.5-4.5 and where (a+b)/c=0.5-15.

As used herein, the term “LIRAP” refers to a lithium rich antiperovskiteand is used synonymously with “LOC” or “Li₃OCI”. The composition ofLIRAP is aLi₂O+bLiX+cLiOH+dAl₂O₃ where X═Cl, Br, and/or I, a/b=7-9,c/a=0.01-1, d/a=0.001-0.1.

As used herein, “LSS” refers to lithium silicon sulfide which can bedescribed as Li₂S—SiS₂, Li—SiS₂, Li—S—Si, and/or a catholyte consistingessentially of Li, S, and Si. LSS refers to an electrolyte materialcharacterized by the formula Li_(x)Si_(y)S_(z) where 0.33≤x≤0.5,0.1≤y≤0.2, 0.4≤z≤0.55, and it may include up to 10 atomic % oxygen. LSSalso refers to an electrolyte material comprising Li, Si, and S. In someexamples, LSS is a mixture of Li₂S and SiS₂. In some examples, the ratioof Li₂S:SiS₂ is 90:10, 85:15, 80:20, 75:25, 70:30, 2:1, 65:35, 60:40,55:45, or 50:50 molar ratio. LSS may be doped with compounds such asLi_(x)PO_(y), Li_(x)BO_(y), Li₄SiO₄, Li₃MO₄, Li₃MO₃, PS_(x), and/orlithium halides such as, but not limited to, LiI, LiCl, LiF, or LiBr,wherein 0<x≤5 and 0<y≤5.

As used herein, “LTS” refers to a lithium tin sulfide compound which canbe described as Li₂S—SnS₂, Li₂S—SnS, Li—S—Sn, and/or a catholyteconsisting essentially of Li, S, and Sn. The composition may beLi_(x)Sn_(y)S_(z) where 0.25≤x≤0.65, 0.05≤y≤0.2, and 0.25≤z≤0.65. Insome examples, LTS is a mixture of Li₂S and SnS₂ in the ratio of 80:20,75:25, 70:30, 2:1, or 1:1 molar ratio. LTS may include up to 10 atomic %oxygen. LTS may be doped with Bi, Sb, As, P, B, Al, Ge, Ga, and/or In.As used herein, “LATS” refers to LTS, as used above, and furthercomprising Arsenic (As).

As used herein, “LXPS” refers to a material characterized by the formulaLi_(a)MP_(b)S_(c), where M is Si, Ge, Sn, and/or Al, and where 2≤a≤8,0.5≤b≤2.5, 4≤c≤12. “LSPS” refers to an electrolyte materialcharacterized by the formula L_(a)SiP_(b)S_(c), where 2≤a≤8, 0.5≤b≤2.5,4≤c≤12. LSPS refers to an electrolyte material characterized by theformula LaSiPbSc, wherein, where 2≤a≤8 , 0.5≤b≤2.5 ,4 ≤c≤12, d<3.Exemplary LXPS materials are found, for example, in International PatentApplication No. PCT/US14/38283, SOLID STATE CATHOLYTE OR ELECTROLYTE FORBATTERY USING LiAMPBSC (M=SI, GE, AND/OR SN), filed May 15, 2014, andpublished as WO 2014/186634, on Nov. 20, 2014, which is incorporated byreference herein in its entirety. Exemplary LXPS materials are found,for example, in U.S. patent application Ser. No. 14/618,979, filed Feb.10, 2015, and published as Patent Application Publication No.2015/0171465, on Jun. 18, 2015, which is incorporated by referenceherein in its entirety. When M is Sn and Si—both are present—the LXPSmaterial is referred to as LSTPS. As used herein, “LSTPSO” refers toLSTPS that is doped with, or has, O present. In some examples, “LSTPSO”is a LSTPS material with an oxygen content between 0.01 and 10 atomic %.“LSPS” refers to an electrolyte material having Li, Si, P, and Schemical constituents. As used herein “LSTPS” refers to an electrolytematerial having Li, Si, P, Sn, and S chemical constituents. As usedherein, “LSPSO” refers to LSPS that is doped with, or has, O present. Insome examples, “LSPSO” is a LSPS material with an oxygen content between0.01 and 10 atomic %. As used herein, “LATP,” refers to an electrolytematerial having Li, As, Sn, and P chemical constituents. As used herein“LAGP” refers to an electrolyte material having Li, As, Ge, and Pchemical constituents. As used herein, “LXPSO” refers to a catholytematerial characterized by the formula Li_(a)MP_(b)S_(c)O_(d), where M isSi, Ge, Sn, and/or Al, and where 2≤a≤8, 0.5≤b≤2.5, 4≤c≤12, d≤3. LXPSOrefers to LXPS, as defined above, and having oxygen doping at from 0.1to about 10 atomic %. LPSO refers to LPS, as defined above, and havingoxygen doping at from 0.1 to about 10 atomic %.

As used herein, “LPS” refers to an electrolyte having Li, P, and Schemical constituents. As used herein, “LPSO” refers to LPS that isdoped with or has O present. In some examples, “LPSO” is a LPS materialwith an oxygen content between 0.01 and 10 atomic %. LPS refers to anelectrolyte material that can be characterized by the formulaLi_(x)P_(y)S_(z) where 0.33≤x≤0.67, 0.07≤y≤0.2 and 0.4≤z≤0.55. LPS alsorefers to an electrolyte characterized by a product formed from amixture of Li₂S:P₂S₅ wherein the molar ratio is 10:1, 9:1, 8:1, 7:1, 6:15:1, 4:1, 3:1, 7:3, 2:1, or 1:1. LPS also refers to an electrolytecharacterized by a product formed from a mixture of Li₂S:P₂S₅ whereinthe reactant or precursor amount of Li₂S is 95 atomic % and P₂S₅ is 5atomic %. LPS also refers to an electrolyte characterized by a productformed from a mixture of Li₂S:P₂S₅ wherein the reactant or precursoramount of Li₂S is 90 atomic % and P₂S₅ is 10 atomic %. LPS also refersto an electrolyte characterized by a product formed from a mixture ofLi₂S:P₂S₅ wherein the reactant or precursor amount of Li₂S is 85 atomic% and P₂S₅ is 15 atomic %. LPS also refers to an electrolytecharacterized by a product formed from a mixture of Li₂S:P₂S₅ whereinthe reactant or precursor amount of Li₂S is 80 atomic % and P₂S₅ is 20atomic %. LPS also refers to an electrolyte characterized by a productformed from a mixture of Li₂S:P₂S₅ wherein the reactant or precursoramount of Li₂S is 75 atomic % and P₂S₅ is 25 atomic %. LPS also refersto an electrolyte characterized by a product formed from a mixture ofLi₂S:P₂S₅ wherein the reactant or precursor amount of Li₂S is 70 atomic% and P₂S₅ is 30 atomic %. LPS also refers to an electrolytecharacterized by a product formed from a mixture of Li₂S:P₂S₅ whereinthe reactant or precursor amount of Li₂S is 65 atomic % and P₂S₅ is 35atomic %. LPS also refers to an electrolyte characterized by a productformed from a mixture of Li₂S:P₂S₅ wherein the reactant or precursoramount of Li₂S is 60 atomic % and P₂S₅ is 40 atomic %.

As used herein, the term “rational number” refers to any number whichcan be expressed as the quotient or fraction (e.g., p/q) of two integers(e.g., p and q), with the denominator (e.g., q) not equal to zero.Example rational numbers include, but are not limited to, 1, 1.1, 1.52,2, 2.5, 3, 3.12, and 7.

As used herein, the phrase “lithium stuffed garnet” refers to oxidesthat are characterized by a crystal structure related to a garnetcrystal structure. U.S. Patent Application Publication No. U.S.2015/0099190, which published Apr. 9, 2015 and was filed Oct. 7, 2014 as14/509,029, is incorporated by reference herein in its entirety. Thisapplication describes Li-stuffed garnet solid-state electrolytes used insolid-state lithium rechargeable batteries. These Li-stuffed garnetsgenerally having a composition according toLi_(A)La_(B)M′_(C)M″_(D)Zr_(E)O_(F),Li_(A)La_(B)M′_(C)M″_(D)Ta_(E)O_(F), orLi_(A)La_(B)M′_(C)M″_(D)Nb_(E)O_(F), wherein 4<A<8.5, 1.5<B<4, 0≤C≤2,0≤D≤2; 0≤E≤2.5, 10<F<13, and M′ and M″ are each, independently in eachinstance selected from Ga, Al, Mo, W, Nb, Sb, Ca, Ba, Sr, Ce, Hf, Rb,and Ta, or Li_(a)La_(b)Zr_(c)Al_(d)Me″_(e)O_(f), wherein 5<a<8.5; 2<b<4;0≤c≤2.5; 0≤d≤2; 0≤e<2, and 10<f<13 and Me″ is a metal selected from Ga,Nb, Ta, V, W, Mo, and Sb and as otherwise described in U.S. PatentApplication Publication No. U.S. 2015/0099190. As used herein,lithium-stuffed garnets, and garnets, generally, include, but are notlimited to, Li_(7.0)La₃(Zr_(t1)+Nb_(t2)+Ta_(t3))O₁₂+0.35Al₂O₃; wherein(t1+t2+t3=2) so that the La:(Zr/Nb/Ta) ratio is 3:2. Also, garnets usedherein include, but are not limited to, Li_(x)La₃Zr₂O_(F)+yAl₂O₃,wherein x ranges from 5.5 to 9; and y ranges from 0.05 to 1. In theseexamples, subscripts x, y, and F are selected so that the garnet ischarge neutral. In some examples xis 7 and y is 1.0. In some examples, xis 5 and y is 1.0. In some examples, x is 6 and y is 1.0. In someexamples, x is 8 and y is 1.0. In some examples, x is 9 and y is 1.0. Insome examples x is 7 and y is 0.35. In some examples, x is 5 and y is0.35. In some examples, x is 6 and y is 0.35. In some examples, x is 8and y is 0.35. In some examples, x is 9 and y is 0.35. In some examplesx is 7 and y is 0.7. In some examples, x is 5 and y is 0.7. In someexamples, x is 6 and y is 0.7. In some examples, x is 8 and y is 0.7. Insome examples, x is 9 and y is 0.7. In some examples x is 7 and y is0.75. In some examples, x is 5 and y is 0.75. In some examples, x is 6and y is 0.75. In some examples, x is 8 and y is 0.75. In some examples,x is 9 and y is 0.75. In some examples x is 7 and v is 0.8. In someexamples, x is 5 and y is 0.8. In some examples, x is 6 and y is 0.8. Insome examples, x is 8 and y is 0.8. In some examples, x is 9 and y is0.8. n some examples x is 7 and y is 0.5. in some examples, x is 5 and yis 0.5. in some examples, xis 6 and y is 0.5. In some examples, xis 8and y is 0.5. In some examples, x is 9 and y is 0.5. In some examples xis 7 and y is 0.4. In some examples, x is 5 and y is 0.4. In someexamples, x is 6 and y is 0.4. In some examples, x is 8 and y is 0.4. Insome examples, x is 9 and y is 0.4. In some examples x is 7 and y is0.3. In some examples, x is 5 and y is 0.3. n some examples, x is 6 andy is 0.3. In some examples, x is 8 and y is 0.3. In some examples, x is9 and y is 0.3. In some examples xis 7 and y is 0.22. In some examples,x is 5 and y is 0.22. In some examples, x is 6 and y is 0.22. In someexamples, x is 8 and y is 0.22. n some examples, x is 9 and y is 0.22.Also, garnets as used herein include, but are not limited to,Li_(x)La₃Zr₂O₁₂+yAl₂O₃. In one embodiment, the Li-stuffed garnet hereinhas a composition of Li₇Li₃Zr₂O₁₂. In another embodiment, the Li-stuffedgarnet herein has a composition of Li₇Li₃Zr₂O₁₂. Al₂O₃. In yet anotherembodiment, the Li-stuffed garnet herein has a composition ofLi₇Li₃Zr₂O₁₂.0.22Al₂O₃. In yet another embodiment, the Li-stuffed garnetherein has a composition of Li₇Li₃Zr₂O₁₂.0.35Al₂O₃. In certain otherembodiments, the Li-stuffed garnet herein has a composition ofLi₇Li₃Zr₂O₁₂.0.5Al₂O₃. In another embodiment, the Li-stuffed garnetherein has a composition of Li₇Li₃Zr₂O₁₂.0.75Al₂O₃.

As used herein, garnet does not include YAG-garnets (i.e., yttriumaluminum garnets, or, e.g., Y₃Al₅O₁₂). As used herein, garnet does notinclude silicate-based garnets such as pyrope, almandine, spessartine,grossular, hessonite, or cinnamon-stone, tsavorite, uvarovite andandradite and the solid solutions pyrope-almandine-spessarite anduvarovite-grossular-andradite. Garnets herein do not includenesosilicates having the general formula X₃Y₂(SiO₄)₃ wherein X is Ca,Mg, Fe, and, or, Mn; and Y is Al, Fe, and, or, Cr.

As used herein, the phrase “inorganic solid-state electrolyte” is usedinterchangeably with the phrase “solid separator” refers to a materialwhich does not include carbon and which conducts atomic ions (e.g., butdoes not conduct electrons. An inorganic solid-state electrolyte is asolid material suitable for electrically isolating the positive andnegative electrodes of a lithium secondary battery while also providinga conduction pathway for lithium ions. Example inorganic solid-stateelectrolytes include oxide electrolytes and sulfide electrolytes, whichare further defined below. Non-limiting example sulfide electrolytes arefound, for example, in U.S. Pat. No. 9,172,114, which issued Oct. 27,2015, and also in U.S. Provisional Patent Application No. 62/321,428,filed Apr. 12, 2016. Non-limiting example oxide electrolytes are found,for example, in US Patent Application Publication No. 2015-0200420 A1,which published Jul. 16, 2015. n some examples, the inorganicsolid-state electrolyte also includes a polymer.

As used herein, examples of the materials in International PatentApplication PCT Patent Application Nos. PCT/US2014/059575 andPCT/US2014/059578, GARNET MATERIALS FOR LI SECONDARY BATTERIES ANDMETHODS OF MAKING AND USING GARNET MATERIALS, filed Oct. 7, 2014, whichis incorporated by reference herein in its entirety, are suitable foruse as the inorganic solid-state electrolytes described herein, also asthe oxide based electrolytes, described herein, and also as the garnetelectrolytes, described herein.

As used herein the phrase “casting a film” refers to the process ofdelivering or transferring a liquid or a slurry into a mold, or onto asubstrate, such that the liquid or the slurry forms, or is formed into,a film. Casting may be done via doctor blade, Meyer rod, comma coater,gravure coater, microgravure, reverse comma coater, slot dye, slipand/or tape casting, and other methods known to those skilled in theart.

As used herein, the phrase “slot casting” refers to a deposition processwhereby a substrate is coated, or deposited, with a solution, liquid,slurry, or the like by flowing the solution, liquid, slurry, or thelike, through a slot or mold of fixed dimensions that is placed adjacentto, in contact with, or onto the substrate onto which the deposition orcoating occurs. In some examples, slot casting includes a slot openingof about 1 μm to 100 μm in slot opening width.

As used herein, the phrase “dip casting” or “dip coating” refers to adeposition process whereby substrate is coated, or deposited, with asolution, liquid, slurry, or the like, by moving the substrate into andout of the solution, liquid, slurry, or the like, often in a verticalfashion.

As used herein the term “making” refers to the process or method offorming or causing to form the object that is made. For example, makingan energy storage electrode includes the process, process steps, ormethod of causing the electrode of an energy storage device to beformed. The end result of the steps constituting the making of theenergy storage electrode is the production of a material that isfunctional as an electrode.

As used herein, the phrase “providing” refers to the provision of,generation or, presentation of, or delivery of that which is provided.

As used herein, the phrase “garnet-type electrolyte” refers to anelectrolyte that includes a garnet or lithium stuffed garnet materialdescribed herein as the ionic conductor.

As used herein, the phrase “antiperovskite” refers to an electrolytecharacterized by the antiperovskite crystal structure. Exemplaryantiperovskites are found, for example, in U.S. patent application Ser.No. 13/777,602, filed Feb. 26, 2013. Antiperovskites include but are notlimited to Li₃OBr or Li₃OCl.

As used herein, the phrase “subscripts and molar coefficients in theempirical formulas are based on the quantities of raw materialsinitially batched to make the described examples” means the subscripts,(e.g, 7, 3, 2, 12 in Li₇La₃Zr₂O₁₂ and the coefficient 0.35 in 0.35Al₂O₃)refer to the respective elemental ratios in the chemical precursors(e.g., LiOH, La₂O₃, ZrO₂, Al₂O₃) used to prepare a given material,(e.g., Li₇La₃Zr₂O₁₂.0.35Al₂O₃). As used here, the phrase “characterizedby the formula” refers to a molar ratio of constituent atoms either asbatched during the process for making that characterized material or asempirically determined.

As used herein, the term “solvent” refers to a liquid that is suitablefor dissolving or solvating a component or material described herein.For example, a solvent includes a liquid, e.g., propylene carbonate,which is suitable for dissolving a component, e.g., the salt, used inthe electrolyte.

As used herein, the phrase “removing a solvent” refers to the processwhereby a solvent is extracted or separated from the components ormaterials set forth herein. Removing a solvent includes, but is notlimited to, evaporating a solvent. Removing a solvent includes, but isnot limited to, using a vacuum or a reduced pressure to drive off asolvent from a mixture, e.g., an unsintered thin film. In some examples,a thin film that includes a binder and a solvent is heated or alsooptionally placed in a vacuum or reduced atmosphere environment in orderto evaporate the solvent to leave the binder, which was solvated, in thethin film after the solvent is removed.

As used herein, the phrase “nitrile” or “nitrile solvent” refers to ahydrocarbon substitueted by a cyano group, or a solvent which includes acyano (i.e., —C≡N) substituent bonded to the solvent. Nitrile solventsmay include dinitrile solvents.

As used herein, the phrase “dinitrile” or “dinitrile solvent” refers toa linear hydrocarbon chain where both ends of the chain are terminatedwith a cyano (i.e., —C≡N) group. Example dinitrile solvents arecharacterized by Formula (I):

wherein:

-   R¹, R², R³, and R⁴ are, independently in each instance, selected    from —CN, —NO₂, —CO₂, —SO₄, —H, —SO₃, —SO₂, —CH₂—SO₃, —CHF—SO₃,    —CF₂—SO₃, —F, —Cl, —Br, and —I; and-   wherein subscript m is an integer from 1 to 1000.

Some exemplary nitrile and dinitrile solvents include, but are notlimited to, acetonitrile, succinonitrile, glutaronitrile, malononitrile,hexanedinitrile (adiponitrile), sebaconitrile, suberonitrile,pimelonitrile, dodecanedinitrile, phthalonitrile,cis/trans-1,2-dicyanocyclohexane, and combinations thereof.

As used herein, the phrase “organic sulfur-including solvent” refers toa solvent selected from ethyl methyl sulfone, dimethyl sulfone,sulfolane, allyl methyl sulfone, butadiene sulfone, butyl sulfone,methyl methanesulfonate, and dimethyl sulfite.

As used herein, the phrase “impermeable to the catholyte” refers to amaterial that allows a low flux of catholyte to permeate, for exampleless than 1 g/cm²/year, through the material, e.g., a solid separator,which is impermeable to the catholyte or its constituent components.

As used herein, the phrase “bonding layer” refers to an ionicallyconductive layer between two other layers, e.g., between the cathode andthe solid separator. Exemplary bonding layers include the gelelectrolytes, and related separator bonding agents, set forth in U.S.Provisional Patent Application No. 62/336,474, filed May 13, 2016, theentire contents of which are herein incorporated by reference in itsentirety for all purposes.

As used herein, the term “HOMO” or “Highest Occupied Molecular Orbital”refers to the energy of the electron occupying the highest occupiedmolecular orbital, as referenced to the vacuum energy. As used herein,the term “LUMO” refers to “Lowest Unoccupied Molecular Orbital.” HOMOand LUMO energy levels are calculated by DFT calculations referenced tothe vacuum level. Unless otherwise specified, the DFT calculations use aB3LYP functional for exchange and correlation and a 6-311++g** basisset.

As used herein, the phrase “lithium transference” refers to theproportion of current carried by lithium ions relative to the totalcurrent. Lithium transference is a number between 0 and 1, inclusive andmay be measured by the Bruce-Vincent method.

As used herein, the phrase “stability window” refers to the voltagerange within which a material exhibits no reaction which materially orsignificantly degrades the material's function in an electrochemicalcell. It may be measured in an electrochemical cell by measuring cellresistance and Coulombic efficiency during charge/discharge cycling. Forvoltages within the stability window (i.e. the working electrode vsreference electrode within the stability window), the increase of cellresistance is low. For example, this resistance increase may be lessthan 1% per 100 cycles.

As used herein, the term “LiBOB” refers to lithium bis(oxalato)borate.

As used herein, the term “LiBETI” refers to lithiumbis(perfluoroethanesulfonyl)imide.

As used herein, the term “LIFSI” refers to lithiumbis(fluorosulfonyl)imide.

As used herein, the term “LiTFSI” refer to lithiumbis-trifluoromethanesulfonimide.

As used herein, voltage is set forth with respect to lithium (i.e., Vvs. Li) metal unless stated otherwise.

As used herein, the term “LiBHI” refers to a combination of LiBH₄ andLiX, wherein X is Br, Cl, I, or a combination thereof

As used herein, the term “LiBNHI” refers to a combination of LiBH₄,LiNH2, and LiX, wherein X is Br, Cl, I, or combinations thereof

As used herein, the term “LiBHCl” refers to a combination of LiBH₄ andLiCl.

As used herein, the term “LiBNHCl” refers to a combination of LiBH₄,LiNH₂, and LiCl.

As used herein, the term “LiBHBr” refers to a combination of LiBH₄ andLiBr.

As used herein, the term “LiBNHBr” refers to a combination of LiBH₄,LiNH₂, and LiBr.

As used herein, viscosity is measured using a Brookfield viscometerDV2T.

As used herein, the term “monolith” refers to a shaped, fabricatedarticle with a homogenous microstructure with no structural distinctionsobserved optically, which has a form factor top surface area between 10cm² and 500 cm².

As used herein, the term “vapor pressure” refers to the equilibriumpressure of a gas above its liquid at the same temperature in a closedsystem. Measurement procedures often consist of purifying the testsubstance, isolating it in a container, evacuating any foreign gas, thenmeasuring the equilibrium pressure of the gaseous phase of the substancein the container at different temperatures. Better accuracy is achievedwhen care is taken to ensure that the entire substance and its vapor areat the prescribed temperature. This is often done, as with the use of anisoteniscope, by submerging the containment area in a liquid bath.

As used herein, the term “lithium salt” refers to a lithium-containingcompound that is a solid at room temperature that at least partiallydissociates when immersed in a solvent such as EMC. Lithium salts mayinclude but are not limited to LiPF₆, LiBOB, LiTFSi, LiFSI, LiAsF₆,LiClO₄, LiI, LiBETI, LiBF₄. As used herein, the term “carbonate solvent”refers to a class of solvents containing a carbonate group C(═O)(O—)₂.Carbonate solvents include but are not limited to ethylene carbonate,dimethyl carbonate, propylene carbonate, diethyl carbonate, ethyl methylcarbonate, dimethyl ethylene carbonate, isobutylene carbonate,nitroethyl carbonate, Monofluoroethylene carbonate, fluoromethylethylene carbonate, 1,2-butylene carbonate, methyl propyl carbonate,isopropyl methyl carbonate, etc.

As used herein, the term “a high voltage-stable catholyte” refers to acatholyte which does not react at high voltage (4.2 V or higher versusLi metal) in a way that materially or significantly degrades the ionicconductivity of the catholyte when held at high voltage at roomtemperature for one week. Herein, a material or significant degradationin ionic conductivity is a reduction in ionic conductivity by an orderof magnitude or more. For example, if the catholyte has an ionicconductivity of 10E-3 S/cm, and when charged to 4.2V or higher thecatholyte has an ionic conductivity of 10E-4 S/cm, then the catholyte isnot stable at 4.2V or higher since its ionic conductivity materially andsignificantly degraded at that voltage.” As used herein, the term “highvoltage” means at least 4.2V versus lithium metal. High voltage may alsorefer to higher voltage, e.g., 4.3, 4.4, 4.5, 4.6, 4.7, 4.8. 4.9, 5.0 Vor higher.

As used herein, the term “chemically compatible” means that two or morematerials or chemicals are chemically compatible with each other if thematerials can be physically exposed to each other and the materials donot react in a way which materially or significantly degrades theelectrochemical performance. Herein, electrochemical performance refersto either ionic conductivity or area-specific resistance (ASR). Amaterial or significant degradation in ionic conductivity is adegradation by an order of magnitude or more. A material or significantdegradation in ASR is a degradation by a factor of 2 or more when heldat room temperature for one week.

As used herein, ASR is measured by electrochemical cycling using Arbinor Biologic unless otherwise specified to the contrary.

As used herein, ionic conductivity is measured by electrical impedancespectroscopy methods known in the art.

B. GENERAL

Set forth herein are battery architectures for batteries which include asolid-state separator which physically isolates the cathode from theanode. These architectures allow, for the first time in a rechargeablelithium battery, the use of electrolytes in the cathode, i.e.,catholytes, that have no stability requirement against lithium metal orgraphite, e.g., high-voltage (greater than 4.3V) stable dinitrileelectrolytes. These electrolytes have advantageous properties includingsafety, lifetime, cyclability, voltage stability, and rate performance.In some examples, set forth herein are devices that include a highvoltage, nitrile, or dinitrile or organic sulfur-includingcathode-electrolyte (i.e., catholyte) which is stable at high oxidationpotentials within the cathode side of an electrochemical device having asolid-state separator. The new battery architectures presented for thefirst time herein are not possible in a conventional Li-ion battery.Conventional battery architectures use catholytes which penetrate theanode space and therefore must be stable and/or passivating at the anodevoltage and also chemically compatible with the anode materials. It isonly by using a solid-state separator that the nitrile and highvoltage-stable catholytes herein can be used practically inelectrochemical devices as catholytes or electrolytes within the cathodespace. In some examples, set forth herein are nitrile catholytes whichare stable at high voltages with respect to lithium but which are notstable at low voltages with respect to lithium. In some examples, setforth herein are organic sulfur-including catholytes which are stable athigh voltages with respect to lithium but which are not stable at lowvoltages (e.g. less than 1.5V or less than 1V) with respect to lithium,meaning that they significantly degrade in impedance or conductivity atroom temperature for one week.

As shown in FIG. 1, in one example, an electrochemical cell (100)includes a positive electrode 101 of 5-200 μm thickness. This electrode101 includes active materials 102 surrounded by a cathode-electrolyte103. Active materials 102 may be present in 20-80 vol %, and thecatholyte may be present in 5-60 vol %. The electrode 101 is layered toa solid separator 104 (e.g., a lithium-stuffed garnet electrolytemonolith or thin film). The solid separator 104 is layered to alithium-metal negative electrode 105. The solid separator 104 may be100nm-100₁1m thick, and the lithium metal negative electrode 105 may be1μm-50 gm thick. The solid separator 104 is impermeable to thecatholyte-electrolyte 103.

In certain examples, the positive electrode is from 30 μm to 300 μmthick. In some examples, the positive electrode is from 40 μm to 200 μmthick. In some of these examples, the positive electrode is about 30 μmthick. In some of these examples, the positive electrode is about 40 μmthick. In some of these examples, the positive electrode is about 50 μmthick. In some of these examples, the positive electrode is about 60 μmthick. In some of these examples, the positive electrode is about 70 μmthick. In some of these examples, the positive electrode is about 80 μmthick. In some of these examples, the positive electrode is about 90 μmthick. In some of these examples, the positive electrode is about 100 μmthick. In some of these examples, the positive electrode is about 110 μmthick. In some of these examples, the positive electrode is about 120 μmthick. In some of these examples, the positive electrode is about 130 μmthick. In some of these examples, the positive electrode is about 140 μmthick. In some of these examples, the positive electrode is about 150 μmthick. In some of these examples, the positive electrode is about 160 μmthick. In some of these examples, the positive electrode is about 170 μmthick. In some of these examples, the positive electrode is about 180 μmthick. In some of these examples, the positive electrode is about 190 μmthick. In some of these examples, the positive electrode is about 200 μmthick. In some of these examples, the positive electrode is about 210 μmthick. In some of these examples, the positive electrode is about 220 μmthick. In some of these examples, the positive electrode is about 230 μmthick. In some of these examples, the positive electrode is about 240 μmthick. In some of these examples, the positive electrode is about 250 μmthick. In some of these examples, the positive electrode is about 260 μmthick. In some of these examples, the positive electrode is about 270 μmthick. In some of these examples, the positive electrode is about 280 μmthick. In some of these examples, the positive electrode is about 290 μmthick. In some of these examples, the positive electrode is about 300 μmthick.

The active material (e.g., a nickel manganese cobalt oxide, i.e., NMC, anickel cobalt aluminum oxide, i.e., NCA, a lithium cobalt oxide, i.e.,LCO, a lithium-rich nickel manganese oxide, i.e., LNMO, FeF₃, CoF₂,CuF₂, CoF₃, and related or functionally equivalent active materials) maybe present in a volume fraction of 20-95%. In some examples, the volumefraction is 50-75 v%. The cathode electrolyte, or catholyte, may bepresent in a volume fraction of 10-50%. In some examples, the catholyteis present in a volume fraction of 20-40 volume %. The solid separatormay be 0.5-100 μm thick. In some examples, the solid separator is 1-30μm thick. The negative electrode may be 3-80 μm thick. In some examples,the negative electrode is 20-50 μm thick in the charged state.

In any of the above examples, the carbon content in the positiveelectrode is less than 5% w/w. In any of the above examples, the bindercontent in the positive electrode is less than 5% w/w.

C. CATHOLYTES AND SOLID SEPARATOR ELECTROLYTES

In some examples, set forth herein is a high voltage-stable catholytewhich includes a solvent and a lithium salt. In some examples, thesolvent is a nitrile solvent. In some examples, the solvent is adinitrile solvent. In yet other examples, the solvent is a combinationof a nitrile and dinitrile solvent. In yet other example the solvent isa combination of a dinitrile and another dinitrile. In yet otherexample, the solvent is an organic sulfur-including solvent. In yetanother example, the solvent is a combination of an organicsulfur-including sovlent and another aprotic solvent.

In some examples, set forth herein is a catholyte which includes anitrile or dinitrile solvent and a lithium salt.

In some of these examples, the solvent in the catholyte is selected fromthe group consisting of from acetonitrile, butyronitrile, benzonitrile,glutaronitrile, hexanenitrile, fluoroacetonitrile, nitroacetonitrile,ethoxy acetonitrile, methoxy acetonitrile, pentanenitrile,propanenitrile, succinonitrile, adiponitrile, iso-butyronitrile,malononitrile and combinations thereof. In certain examples, thecatholyte solvent is fluoromethyl ethylene carbonate, ethylnitroacetate, N-Methylpyrrolidone, y-butyrolactone, ethyl methylsulfone, dimethyl sulfone, sulfolane, allyl methyl sulfone, butadienesulfone, butyl sulfone, methyl methanesulfonate, dimethyl sulfite,dimethyl sulfoxide, dimethylsulfate, 3-methyl-2-oxazolidinone,fluorinated cyclic carbonate, methylene methane disulfonate, methylcyanoacetate. In certain examples, the solvent is acetonitrile. Incertain examples, the solvent is butyronitrile. In certain examples, thesolvent is glutaronitrile. In certain examples, the solvent ishexanenitrile. In certain examples, the solvent is fluoroacetonitrile.In certain examples, the solvent is nitroacetonitrile. In certainexamples, the solvent is iso-butyronitrile. In certain examples, thesolvent is ethoxyacetonitrile. In certain examples, the solvent ispentanenitrile. In certain examples, the solvent is propanenitrile. Incertain examples, the solvent is succinonitrile. In certain examples,the solvent is adiponitrile. In certain examples, the solvent ismalononitrile. In certain examples, the solvent is benzonitrile. Incertain examples, the solvent is methoxyacetonitrile. In certainexamples, the solvent is a combination of succinonitrile andadiponitrile. In certain examples, the solvent is a combination ofsuccinonitrile and glutaronitrile.

In some examples, the electrochemical cell set forth herein includes adinitrile solvent which includes a dinitrile represented by Formula (I):

wherein:

-   -   R¹, R², R³, and R⁴ are, independently in each instance, selected        from —CN, —NO₂, —CO₂, —SO₄, —SO₃, —SO₂, —H, —CH₂—SO₃, —CHF—SO₃,        —CF₂—SO₃, —F, —Cl, —Br, and —I; and    -   subscript m is an integer from 1 to 1000.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —CN.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —NO₂.

In some of the examples herein, R¹, R², and R⁴ are, independently ineach instance, —H or —CO₂.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —SO₄. In some of the examples herein, R¹, R², R³,and R⁴ are, independently in each instance, —H or —SO₃. In some of theexamples herein, R¹, R², R³, and R⁴ are, independently in each instance,—H or —SO₂.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —CH₂—SO₃.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —CHF—SO₃.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, 1'H or —CF₂—SO₃.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —F.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —Cl.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —Br.

Tn some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —I.

Tn some examples herein, the catholyte solvent includes a memberselected from the group consisting of:

and combinations thereof. In certain examples, the solvent is acombination of succinonitrile and adiponitrile. In certain examples, thesolvent is a combination of succinonitrile and glutaronitrile.

In some examples herein, the catholyte solvent includes an organicsulfur-including solvent. In some examples herein, the organicsulfur-including solvent is selected from the group consisting of ethylmethyl sulfone, dimethyl sulfone, sulfolane, allyl methyl sulfone,butadiene sulfone, butyl sulfone, methyl methanesulfonate, and dimethylsulfite.

In some of these examples, the lithium salt is selected from LiPF6,LiBOB, LiTFSi, LiFSI, LiAsF₆, LiClO₄, LiI, LiBF₄, and a combinationthereof. In certain examples, the lithium salt is LiPF₆, In certainexamples, the lithium salt is LiBOB. In certain examples, the lithiumsalt is LiTFSi. In certain examples, the lithium salt is LiBF₄. Incertain examples, the lithium salt is LiClO₄. In certain examples, thelithium salt is LiFSI. In certain examples, the lithium salt is LiAsF₆.In certain examples, the lithium salt is LiClO₄. In certain examples,the lithium salt is LiI. In certain examples, the lithium salt is LiBF₄.

In the examples herein, the catholyte is chemically stable when incontact with a solid separator.

In some of the examples herein, the electrochemical cell furtherincludes a bonding layer which includes a solvent selected from ethylenecarbonate (EC), diethylene carbonate, diethyl carbonate, dimethylcarbonate (DMC), ethyl-methyl carbonate (EMC), tetrahydrofuran (THF),γ-Butyrolactone (GBL), fluoroethylene carbonate (FEC), fluoromethylethylene carbonate (FMEC), trifluoroethyl methyl carbonate (F-EMC),fluorinated 3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane(i.e., 1,1,2,2-tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy)propane(F-EPE)), fluorinated cyclic carbonate (F-AEC), propylene carbonate(PC), dioxolane, acetonitrile (ACN), succinonitrile, adiponitrile,hexanedinitrile, pentanedinitrile, acetophenone, isophorone,benzonitrile, dimethyl sulfate, dimethyl sulfoxide (DMSO) ethyl-methylcarbonate, ethyl acetate, methyl butyrate, dimethyl ether (DME), diethylether, propylene carbonate, dioxolane, glutaronitrile, gammabutyrolactone, and combinations thereof. In some examples, the solventis ethylene carbonate (EC). In some examples, the solvent is diethylenecarbonate. In some examples, the solvent is dimethyl carbonate (DMC). Insome examples, the solvent is ethyl-methyl carbonate (EMC). In someexamples, the solvent is tetrahydrofuran (THF). In some examples, thesolvent is γ-Butyrolactone (GBL). In some examples, the solvent isfluoroethylene carbonate (FEC). In some examples, the solvent isfluoromethyl ethylene carbonate (FMEC). In some examples, the solvent istrifluoroethyl methyl carbonate (F-EMC). In some examples, the solventis fluorinated 3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane(i.e., 1,1,2,2-tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy)propane(F-EPE)). In some examples, the solvent is fluorinated cyclic carbonate(F-AEC). In some examples, the solvent is propylene carbonate (PC). Insome examples, the solvent is dioxolane. In some examples, the solventis acetonitrile (ACN). In some examples, the solvent is succinonitrile.In some examples, the solvent is adiponitrile/hexanedinitrile. In someexamples, the solvent is acetophenone. In some examples, the solvent isisophorone. In some examples, the solvent is benzonitrile. In someexamples, the solvent is dimethyl sulfate. In some examples, the solventis dimethyl sulfoxide (DMSO). In some examples, the solvent is ethylacetate. In some examples, the solvent is methyl butyrate. In someexamples, the solvent is dimethyl ether (DME). In some examples, thesolvent is diethyl ether. In some examples, the solvent is dioxolane. Insome examples, the solvent is glutaronitrile. In some examples, thesolvent is gamma butyrolactone. In some examples, the solvent is acombination of any solvents mentioned above. This bonding layer may beused to adhere or bond the cathode to the solid separator.

In some of the examples herein, the electrochemical cell furtherincludes a bonding layer which includes a lithium salt in the bondinglayer is selected from LiPF₆, LiBOB, LFTSi, or combinations thereof. Incertain examples, the lithium salt in the bonding layer is LiPF₆ at aconcentration of 0.5 M to 2 M. In certain examples, wherein the lithiumsalt in the bonding layer is LiTFSI at a concentration of 0.5 M to 2 M.

In some of the examples herein, the catholyte solvent is a solventhaving a permittivity of greater than 30. In certain of these examples,the catholyte solvent is a dinitrile-containing solvent.

In some of the examples herein, the catholyte solvent is a solventhaving a viscosity of greater than 0.01 cP and less than 10 cP at 25° C.

In some of the examples herein, the catholyte solvent is a solventhaving a flash point of greater than 50° C. and less than 400° C.

In some of the examples herein, the catholyte solvent is a solventhaving a melting point higher than -50° C. and lower than 30° C.

In some of the examples herein, the catholyte solvent is a solventhaving a boiling point of greater than 80° C.

In some of the examples herein, the catholyte solvent is a solventhaving a HOMO level of more than 7.2 eV below the vacuum level ascalculated by DFT (density fuctional theory) with a B3LYP (Becke,3-parameter. Lee-Yang-Parr) exchange-correlation functional and6-311++G** basis set. In some examples, the HOMO level is more than 7.8eV below the vacuum level as calculated by DFT with a B3LYPexchange-correlation functional and 6-311++G** basis set. In someexamples, the HOMO level is more than 8.2 eV below the vacuum level ascalculated by DFT with a B3LYP exchange-correlation functional and6-311++G** basis set. For example, for succinonitrile, the HOMO=−9.65eV, and LUMO=−0.92 eV; for ethyl methyl sulfone HOMO=−8.08 eV,LUMO=−0.62 eV.

In some of the examples herein, the catholyte solvent is a solvent ispolar and aprotic.

In some of the examples herein, the catholyte has a lithium transferencenumber of greater than 0.2.

In some of the examples herein, the catholyte has a total ionicconductivity of greater than le-4S/cm at 25° C.

In some of the examples herein, the catholyte solvent has a vaporpressure of lower than 2 Torr at 20° C. In some of the examples herein,the catholyte solvent has a vapor pressure of lower than 0.2 Torr at 20°C. In some of the examples herein, the catholyte solvent has a vaporpressure of lower than 2e-2 Torr at 20° C.

In some of the examples herein, the catholyte solvent has a boilingpoint of greater than 80° C.

In some of the examples herein, the catholyte solvent has a boilingpoint of greater than 250° C.

In some of the examples herein, the catholyte solvent has a viscosity ofless than 10 centipoise (cP) at 25° C.

In some of the examples herein, the catholyte further comprises acarbonate solvent in addition to the nitrile or dinitrile solvent. Insome examples, the catholyte further comprises a solvent selected fromethylene carbonate (EC), diethylene carbonate, diethyl carbonate,dimethyl carbonate (DMC), ethyl-methyl carbonate (EMC), tetrahydrofuran(THF), γ-Butyrolactone (GBL), fluoroethylene carbonate (FEC),fluoromethyl ethylene carbonate (FMEC), trifluoroethyl methyl carbonate(F-EMC), fluorinated3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane/1,1,2,2-tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy)propane(F-EPE), fluorinated cyclic carbonate (F-AEC), propylene carbonate (PC),dioxolane, acetonitrile (ACN), succinonitrile, malononitrile,hexanedinitrile (adiponitrile), pentanedinitrile (glutaronitrile),acetophenone, isophorone, benzonitrile, dimethyl sulfate, dimethylsulfoxide (DMSO) ethyl-methyl carbonate, ethyl acetate, methyl butyrate,dimethyl ether (DME), diethyl ether, propylene carbonate, dioxolane,glutaronitrile, gamma butyrolactone, or combinations thereof. In some ofthe examples herein, the catholyte further comprises a carbonate solventin addition to the organic sulfur-including solvent. In some examples,the catholyte comprises organic sulfur-including solvent and ethylenecarbonate in a ratio of about 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2, or9:1.

In some of the examples herein, the catholyte solvent is stable up to4.7V v. Lithium. In some of the examples herein, the catholyte solventis stable up to 4.5V v. Lithium. In some of the examples herein, thecatholyte solvent is stable up to 4.4V v. Lithium. In some examplesherein, the catholyte solvent is stable up to 4.2V v. Lithium.

In some of the examples herein, the catholyte solvent is stable down to1.5V.

In some of the examples herein, the catholyte solvent includes a nitrilerepresented by Formula (I):

wherein:

-   -   R¹, R², R³, and R⁴ are, independently in each instance, selected        from —CN, —NO₂, —CO₂, —SO₄, —SO₃, —SO₂, —CH₂—SO₃, —CHF—SO₃,        —CF₂—SO₃, —H, —F, —Cl, —Br, and —I;

and wherein subscript m is an integer from 1 to 1000.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —CN.

In some of the examples herein, R¹, R², and R⁴ are, independently ineach instance, —H or —NO₂.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —CO₂.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —SO₄. In some of the examples herein, R¹, R², R³,and R⁴ are, independently in each instance, —H or —SO₃. In some of theexamples herein, R¹, R², R³, and R⁴ are, independently in each instance,—H or —SO₂.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —CH₂—SO₃.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —CHF—SO₃.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —CF₂—SO₃.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —F.

In some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —Cl.

Tn some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —Br.

Tn some of the examples herein, R¹, R², R³, and R⁴ are, independently ineach instance, —H or —I.

Tn certain examples, subscript m is an integer from 1 to 1000. In someof the examples, subscript m is an integer from 1 to 100. In some of theexamples, subscript m is an integer from 1 to 10. In some of theexamples, subscript m is an integer from 1 to 5. In some of theexamples, subscript m is an integer from 1 to 4. In some of theexamples, subscript m is an integer from 1 to 3. In some of theexamples, subscript m is an integer from 1 to 2. n some of the examples,subscript m is 1.

In certain other examples, subscript m is 1. In certain other examples,subscript m is 2. In certain other examples, subscript m is 3. Incertain other examples, subscript m is 4. In certain other examples,subscript m is 5. In certain other examples, subscript m is 6. Incertain other examples, subscript m is 7. In certain other examples,subscript m is 8. In certain other examples, subscript m is 9. Incertain other examples, subscript m is 10. In certain other examples,subscript m is 11. In certain other examples, subscript m is 12. Incertain other examples, subscript m is 13. In certain other examples,subscript m is 14. In certain other examples, subscript m is 15. Incertain other examples, subscript m is 16. In certain other examples,subscript m is 17. In certain other examples, subscript m is 18. Incertain other examples, subscript m is 19. In certain other examples,subscript m is 20.

In some examples herein, the catholyte includes a solvent selected fromthe group consisting of

and combinations thereof. In some examples, the solvent includes bothsuccinonitrile and glutaronitrile. In other examples, the solventincludes succinonitrile and adiponitrile.

In some examples, the dinitrile of Formula I has a total ionicconductivity of greater than 1e-4 S/cm at room temperature.

In some examples, the dinitrile is malononitrile, succinonitrile,glutaronitrile, hexanedinitrile (adipodinitrile), sebaconitrile,subernitrile, pimelonitrile, and dodecanedinitrile, phthalonitrile orcis/trans-1,2-dicyanocyclohexane, or combinations thereof.

In some examples, the lithium salt is selected from LiPF₆, LiBH₄, LiBOB,LiBETI, LiTFSi, LiBF₄, LiClO₄, LiFSI, LiAsF₆, LiClO₄, LiI, LiBF₄, andcombination thereof.

In some examples, the lithium salt is selected from LiPF₆, LiBH₄, LiBOB,LiBETI, LiBF₄, LiAsF₆, LIFSI, LiTFSI, LiClO₄, and combinations thereof

In some examples, the lithium salt is present in the dinitrile solventat a concentration of about 5-20 mol %.

In some examples, a lithium salt is present in the dinitrile solvent ata concentration of about 12 mol %.

In some examples, the catholyte further comprises a carbonate solvent.

In some examples, the catholyte comprises LiBF4, LiCF3SO3, LiN(CF3SO2)2,or a combination thereof.

In some examples, the catholyte solvent is a combination as follows:

wherein coefficients X, Y, and Z refer to the respective molar amountsof each of acetonitrile, succinonitrile, and glutaronitrile. in someexamples, X is 0, Y is 0.87 and Z is 0.13.

In some examples, the catholyte further includes LiBF₄ or LiN(CF₃SO₂)₂.

In some examples, the catholyte further includes an additives such as VC(vinylene carbonate), VEC (vinyl ethylene carbonate), succinicanhydride, PES (prop-1-ene, 1-3 sultone), tris(trimethylsilyl)phosphite, ethylene sulfate, PBF, TMS (1,3-propylene sulfate), methylenemethanedisulfonate (MMDS), lithium nitrate, propylene sulfate,trimethoxyboroxine, FEC, combinations thereof, and the like.

In some examples, the catholyte further includes VC.

In some examples, the catholyte further includes VEC.

In some examples, the catholyte further includes succinic anhydride.

In some examples, the catholyte further includes PES.

In some examples, the catholyte further includes ethylene sulfate.

In some examples, the catholyte further includes PBF.

In some examples. the catholyte further includes TMS

In some examples, the catholyte further includes propylene sulfate.

In some examples, the catholyte further includes trimethoxyboroxine.

In some examples, the catholyte further includes MMDS.

In some examples, the catholytes here are paired with, laminated to,adjoined, or bonded to a solid separator. In some examples, the solidseparator is a Li⁺ conducting solid-state electrolyte material useful asthe separator. Separator materials include those that are stable tolithium metal, including sulfides (Li₂S—SiS₂—LiX, Li₂S—B₂S₃—LiX,Li₂S—P₂S₅—LiX, Li₂S—SnS₂—LiX, Li₂S—Al₂S₃—LiX, and combinations thereof),borohydrides (LiBH₄—LiX, LiNH₂—LiX, LiBH₄—LiNH₂—LiX, and combinationsthereof). LiPON, Li-stuffed garnet, lithium-rich antiperovskite, orLISICON materials. In some examples, the separators is not stable incontact with metal lithium. In some examples, the separator is aperovskite (LLTO), a phosphate (LATP, LAGP), or a Li-β-Al₂O₃.

In addition to dinitrile materials, such as but not limited to,malononitrile, succinonitrile, glutaronitrile, hexanedinitrile(adiponitrile), sebaconitrile, suberonitrile, pimelonitrile,dodecanedinitrile, and the like), some catholyte solvents herein includepolar solvents with nitrile functionalities such as acetonitrile,butyronitrile, benzonitrile, hexanenitrile, fluoroacetonitrile,nitroacetonitrile, ethoxyacetonitrile, pentanenitrile, propanenitrile,iso-butyronitrile, and the like. In some examples, solvents may alsoinclude aprotic liquids with electron withdrawing groups such asfluorine (FEC, F-AEC, F-EPE, F-EMC, TTE). In some examples, solvents mayalso include aprotic liquids with a low HOMO level as calculated bydensity functional theory (DFT). In some other examples, solvents mayalso include MMDS, methyl pivalate, 1,2 dioxane, and sulfolane. In someof these examples, the oxidative stability of the dinitrile is relatedto its HOMO. As the HOMO of the dinitrile decreases, or is a higher(less negative) value, it is easier to oxidize the solvent.

In some examples herein, the lithium salts may include those known inthe art such as, but not limited to, LiPF₆, LiBOB, LiBETI, LiBF₄,LiAsF₆, LiFSI, LiTFSI, LiClO₄, and combinations thereof.

In some examples herein, the catholyte comprises 0.57:0.43glutaronitrile:succinonitrile (mol/mol) and 7 mol % LiBF₄.

In some examples herein, the catholyte comprises 0.3:0.7 ethylenecarbonate: sulfolane (v/v) and 1 M LiPF6.

D. ELECTROCHEMICAL DEVICES

In some examples, set forth herein is an electrochemical cell whichincludes a catholyte set forth herein.

In some examples, set forth herein is an electrochemical cell whichincludes a catholyte set forth herein which includes a dinitrile solventand a lithium salt.

In some examples, set forth herein is an electrochemical cell whichincludes a catholyte set forth herein which includes a nitrile solventand a lithium salt.

In some examples, set forth herein is an electrochemical cell whichincludes a catholyte set forth herein which includes an organicsulfur-including solvent and a lithium salt.

In some examples, set forth herein is an electrochemical cell, whichincludes a lithium metal negative electrode, a solid separator, and apositive electrode. In these examples, the positive electrode includesan active material, and a catholyte. In these examples, the catholyteincludes a dinitrile solvent and a lithium salt.

In some examples, the lithium metal negative electrode is a layerlaminated to the solid separator, wherein the solid separator is a layerlaminated to the positive electrode.

In some examples, the lithium metal negative electrode is laminated tothe solid separator, wherein the solid separator is laminated to thepositive electrode.

In some examples, the lithium metal negative electrode is formed insitu.

In some examples, solid separator is impermeable to the catholyte. Inthese examples, the solid separator is dense enough or the catholyte isviscous enough such that the catholyte does not penetrate through thesolid separator. In some of these examples, the solid separator protectsor encapsulates the lithium metal negative electrode and prevents itfrom contacting the dinitrile catholyte.

In some examples, the electrochemical cell includes a bonding layerbetween the positive electrode and the solid separator. In someexamples, the bonding layer comprises a solvent and a lithium salt. Insome examples, the solvent in the bonding layer is selected from thegroup consisting of ethylene carbonate, methylene carbonate, methylethyl carbonate, diethylene carbonate.

In some examples, the electrochemical cell includes a lithium saltselected from LiPF₆, LiBOB, LiTFSi, LiBF₄, LiClO₄, LiAsF₆, LiFSI,LiClO₄, LiI, and a combination thereof.

In certain examples, the bonding layer further comprises a polymerselected from the group consisting of polyacrylonitrile (PAN),polypropylene, polyethylene oxide (PEO), polymethyl methacrylate (PMMA),polyvinyl chloride (PVC), polyvinyl pyrrolidone (PVP), polyethyleneoxide poly(allyl glycidyl ether) PEO-AGE, polyethylene oxide2-methoxyethoxy)ethyl glycidyl ether (PEO-MEEGE), polyethylene oxide2-methoxyethoxy)ethyl glycidyl poly(allyl glycidyl ether)(PEO-MEEGE-AGE), polysiloxane, polyvinylidene fluoride (PVdF),polyvinylidene fluoride hexafluoropropylene (PVdF-HFP), and rubbers suchas ethylene propylene (EPR), nitrile rubber (NPR),styrene-butadiene-rubber (SBR), polybutadiene polymer, polybutadienerubber (PB), polyisobutadiene rubber (PIB), polyisoprene rubber (PI),polychloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR),polyethyl acrylate (PEA), polyvinylidene fluoride (PVDF), andpolyethylene (e.g., low density linear polyethylene). In some examples,the polymer in the bonding layer is polyacrylonitrile (PAN) orpolyvinylidene fluoride hexafluoropropylene (PVdF-HFP). In someexamples, the polymer in the bonding layer is selected from the groupconsisting of PAN, PVdF-HFP, PVDF-HFP and PAN, PMMA, PVC, PVP, PEO, andcombinations thereof In certain examples, the polymer ispolyacrylonitrile (PAN). In certain examples, the polymer ispolypropylene. In certain examples, the polymer is polyethylene oxide(PEO). In certain examples, the polymer is polymethyl methacrylate(PMMA). In certain examples, the polymer is polyvinyl chloride (PVC). Incertain examples, the polymer is polyvinyl pyrrolidone (PVP). In certainexamples, the polymer is polyethylene oxide poly(allyl glycidyl ether)PEO-AGE. In certain examples, the polymer is polyethylene oxide2-methoxyethoxy)ethyl glycidyl ether (PEO-MEEGE). In certain examples,the polymer is polyethylene oxide 2-methoxyethoxy)ethyl glycidylpoly(allyl glycidyl ether) (PEO-MEEGE-AGE). In certain examples, thepolymer is polysiloxane. In certain examples, the polymer ispolyvinylidene fluoride (PVDF). In certain examples, the polymer ispolyvinylidene fluoride hexafluoropropylene (PVdF-HFP). In certainexamples, the polymer is a rubber such as ethylene propylene (EPR),nitrile rubber (NPR), styrene-butadiene-rubber (SBR), polybutadienepolymer, polybutadiene rubber (PB), polyisobutadiene rubber (PIB),polyisoprene rubber (PI), polychloroprene rubber (CR),acrylonitrile-butadiene rubber (NBR), and polyethyl acrylate (PEA). Insome examples, the polymer is polyethylene (e.g., low density linearpolyethylene). In some examples, the polymer is a combination of anypolymers mentioned above. In some examples, the solvent in the bondinglayer is selected from ethylene carbonate (EC), diethylene carbonate,diethyl carbonate, dimethyl carbonate (DMC), ethyl-methyl carbonate(EMC), tetrahydrofuran (THF), y-Butyrolactone (GBL), fluoroethylenecarbonate (FEC), fluoromethyl ethylene carbonate (FMEC), trifluoroethylmethyl carbonate (F-EMC), fluorinated3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane/1,1,2,2-tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy)propane(F-EPE), fluorinated cyclic carbonate (F-AEC), propylene carbonate (PC),dioxolane, acetonitrile (ACN), succinonitrile, adiponitrile(hexanedinitrile), glutaronitrile (pentanedinitrile), acetophenone,isophorone, benzonitrile, dimethyl sulfate, dimethyl sulfoxide (DMSO)ethyl-methyl carbonate, ethyl acetate, methyl butyrate, dimethyl ether(DME), diethyl ether, propylene carbonate, dioxolane, gammabutyrolactone, or combinations thereof. In some of these examples, thesolvent in the bonding layer is a 1:1 w/w mixture of EC:PC. In some ofthese examples, the lithium salt in the bonding layer is selected fromLiPF₆, LiBOB, LFTSi, or combinations thereof. In some of these examples,the lithium salt in the bonding layer is LiPF₆ at a concentration of 0.5M to 2M. In some of these examples, the lithium salt in the bondinglayer is LiTFSI at a concentration of 0.5 M to 2M. In some of theseexamples, the lithium salt in the bonding layer is present at aconcentration from 0.01 M to 10 M.

In some of these examples, the solid separator is selected from alithium sulfide, a lithium borohydride, a LiPON, a lithium-stuffedgarnet, a lithium-rich antiperovskite, a LISICON, and a combinationthereof. In certain examples, the solid separator is an oxide selectedfrom a lithium-stuffed garnet characterized by the formulaLi_(x)La_(y)Zr_(z)O_(t).qAl₂O₃, wherein 4<x<10, 1<y<4, 1<z<3, 6<t<14,0≤q≤1.

In some of these examples, the solid separator is a lithium-stuffedgarnet doped with Al, Nb, Ga, and/or Ta.

in some of these examples, the solid separator is a lithium-stuffedgarnet characterized by Li_(a)La_(b)Zr_(c)Al_(d)Me″_(e)O_(f), wherein5<a<8.5; 2<b<4; 0≤c≤2.5; 0≤d<2; 0≤e<2, and 10≤f≤13 and Me″ is a metalselected from Nb, Ga, Ta, or combinations thereof.

In some examples, the lithium-stuffed garnet is characterized by theformula Li_(x)La_(y)Zr_(z)O_(t).0.11(Al₂O₃) orLi_(x)La_(y)Zr_(z)O_(t).(Al₂O₃), wherein 5<x<8.5.

In some of these examples, the solid separator is a sulfide orsulfide-halide is selected from LPSI, LSS, SLOPS, LSTPS, SLOBS, andLATS.

In some of these examples, the separator is a sulfide or sulfide-halideis selected from LiBHI, LiBNHI, LiBHC1, LiBNHC1, LiBHBr, LiBNHBr, andcombinations thereof.

In some of these examples, the solid separator is a thin film.

In some of these examples, the solid separator is a monolith.

In some of these examples, the solid separator is a composite of apolymer and a solid electrolyte.

In some of these examples, the catholyte solvent(s) is a solvent havinga permittivity of greater than 30.

In some of these examples, the catholyte solvent(s) is a solvent havinga viscosity of less than 10 cP at 25° C.

In some of these examples, the catholyte solvent(s) is a solvent havinga flash point of greater than 50° C.

In some of these examples, the catholyte solvent(s) is a solvent havinga melting point of lower than 30° C.

In some of these examples, the catholyte solvent(s) is a solvent havinga boiling point of greater than 80° C.

In some of these examples, the catholyte solvent(s) is a solvent havinga HOMO level of more than 7.2 eV below the vacuum level.

In some of these examples, the catholyte solvent(s) is polar andaprotic. In some of these example, the nitrile solvent is selected fromacetonitrile, butyronitrile, benzonitrile, hexanenitrile,fluoroacetonitrile, nitroacetonitrile, malononitrile,ethoxyacetonitrile, pentanenitrile, propanenitrile, andiso-butyronitrile. In some of these example, the dinitrile solventcomprises a member selected from the group consisting of fluoroethylenecarbonate (FEC), fluoromethyl ethylene carbonate (FMEC), trifluoroethylmethyl carbonate (F-EMC), fluorinated3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane1,1,2,2-tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy)propane (F-EPE)),fluorinated cyclic carbonate (F-AEC), and TTE. In some of these example,the dinitrile solvent comprises a member selected from the groupconsisting of MMDS, methyl pivalate, 1,2 dioxane, sulfolane, andcombinations thereof

In some examples, the catholyte has a lithium transference number ofgreater than 0.2.

In some examples, the catholyte has a total ionic conductivity ofgreater than 1e-4S/cm at 25° C.

In some examples, the catholyte solvent has a vapor pressure of lowerthan 2e-2Torr at 20° C., or lower than 0.2Torr at 20° C., or lower than2Torr at 20° C.

In some examples, the catholyte solvent has a boiling point of greaterthan 80° C.

In some examples, the catholyte solvent has a boiling point of greaterthan 250° C.

In some examples, the catholyte solvent has a viscosity of less than 10centipoise (cP) at 25° C.

In some examples, the catholyte further comprises a carbonate solvent.In some of these examples, the catholyte further comprises a solventselected from ethylene carbonate (EC), diethylene carbonate, diethylcarbonate, dimethyl carbonate (DMC), ethyl-methyl carbonate (EMC),tetrahydrofuran (THF), y-Butyrolactone (GBL), fluoroethylene carbonate(FEC), fluoromethyl ethylene carbonate (FMEC), trifluoroethyl methylcarbonate (F-EMC), fluorinated3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane/1,1,2,2-Tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy)propane(F-EPE), fluorinated cyclic carbonate (F-AEC), propylene carbonate (PC),dioxolane, acetonitrile (ACN), succinonitrile, adiponitrile,hexanedinitrile, pentanedinitrile, acetophenone, isophorone,benzonitrile, dimethyl sulfate, dimethyl sulfoxide (DMSO), ethylacetate, methyl butyrate, dimethyl ether (DME), diethyl ether, propylenecarbonate, dioxolane, glutaronitrile, and combinations thereof

In some examples, the catholyte solvent is stable up to 4.7V v. Lithium.In some examples, the catholyte solvent is stable up to 4.5V v. Lithium.In some examples, the catholyte solvent is stable up to 4.4V v. Lithium.

In some examples, the catholyte solvent is stable towards the solidseparator.

In some examples, the catholyte solvent is stable down to 1.5V.

In some examples, the dinitrile solvent is stable up to 4.7V v. Lithium.

In some examples, the dinitrile solvent is stable towards the solidseparator.

In some examples, the dinitrile solvent is stable down to 1.5V.

In some examples herein, the dinitrile of Formula I has a total ionicconductivity of greater than 1e-4S/cm at room temperature.

In some examples herein, the electrochemical cell has a cyclabilitywherein greater than 70% of the initial energy remains at cycle 100 whencycled at a C/3 rate at 30° C.

In some examples herein, the electrochemical cell has a lifetime whereingreater than 70% of the initial energy remains at cycle 100 when cycledat a C/3 rate at 30° C.

In some examples herein, the electrochemical cell has a rate performancewherein greater than 70% of the initial power capability at 50%state-of-charge (SOC) remains at cycle 100 when cycled at a C/3 rate at30° C.

In some examples herein, the electrochemical cell has an oxidationpotential wherein greater than 70% of the initial energy remains atcycle 100 when cycled at a C/3 rate at 30° C.

In some examples herein, the electrochemical cell has an impedance atcycle 100 less than 13% of the initial impedance when cycled at a C/3rate at 30° C.

In any of the electrochemical cells described herein, the dinitrile maybe selected from malononitrile, succinonitrile, glutaronitrile,hexanedinitrile/adiponitrile. sebaconitrile, subernitrile,pimelonitrile, and dodecanedinitrile, phthalonitrile orcis/trans-1,2-dicyanocyclohexane, and combinations thereof.

In any of the electrochemical cells described herein, the lithium saltmay be selected from LiPF₆, LiBH₄, LiBOB, LiBETI, LiTFSi, LiClO₄,LiAsF₆, LIFSI, LiClO₄, LiI, LiBF₄, and combination thereof

In any of the electrochemical cells described herein, the lithium saltmay be selected from LiPF₆, LiBH₄, LiBOB, LiBETI, LiBF₄, LiAsF₆, LIFSI,LiTFSI, LiClO₄, and combinations thereof

In some examples, the lithium salt is present in the dinitrile solventat a concentration of about 5-20 mol %.

In some examples, the lithium salt is present in the dinitrile solventat a concentration of about 12 mol %.

In some examples, the solid separator is a lithium-stuffed-garnet, anLiBHI, Li₃N, a lithium-sulfides, a UPON, a LISON, or a combinationthereof

In some examples, the active material is selected from a nickelmanganese cobalt oxide (NMC), a nickel cobalt aluminum oxide (NCA),Li(NiCoAl)O₂, a lithium cobalt oxide (LCO), a lithium manganese cobaltoxide (LMCO), a lithium nickel manganese cobalt oxide (LMNCO), a lithiumnickel manganese oxide (LNMO), Li(NiCoMn)O₂, LiMn₂O₄, LiCoO₂,LiMn_(2−a)Ni_(a)O₄, wherein a is from 0 to 2, or LiMPO₄, wherein M isFe, Ni, Co, or Mn.

In some examples, the active material is selected from FeF₂, NiF₂,FeO_(x)F_(3−2x), FeF₃, MnF₃, CoF₃, CuF₂ materials, alloys thereof, andcombinations thereof

In some examples, the catholyte herein further includes a carbonatesolvent.

In some examples, the catholyte includes LiBF₄, LiCF₃SO₃, LiN(CF₃SO₂)₂,or a combination thereof.

In some examples, the dinitrile is a combination as follows:

-   -   wherein coefficients X, Y, and Z refer to the respective molar        amounts of each of acetonitrile, succinonitrile, and        glutaronitrile.

In some of these examples, X is 0, Y is 0.87 and Z is 0.13.

In some examples, the electrochemical cell herein includes LiBF₄ orLiN(CF₃SO₂)₂.

In some examples, the electrochemical cell herein includes a solidseparator which includes a lithium-stuffed garnet oxide characterized bythe formula Li_(u)La_(v)Zr_(x)O_(y).zAl₂O₃, wherein

-   -   u is a rational number from 4 to 8;    -   v is a rational number from 2 to 4;    -   x is a rational number from 1 to 3;    -   y is a rational number from 10 to 14;    -   z is a rational number from 0.05 to 1; and    -   wherein u, v, x, y, and z are selected so that the        lithium-stuffed garnet oxide is charge neutral.

In some examples of the above formula, u is selected from 4, 5, 6, 7,and 8; , v is selected from 2, 3, and 4; x is selected from 1, 2, and 3;y is selected from 10, 11, 12, 13, and 14; and z is selected from 0.05,0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7,0.75, 0.8, 0.85, 0.9, 0.95, and 1.

In some examples, the electrochemical cell herein includes a solidseparator which includes a lithium sulfide characterized by one of thefollowing Formula:

-   -   Li_(a)Si_(b)Sn_(c)P_(d)S_(e)O_(f), wherein 2≤a≤8, b+c =1,        0.5≤d≤2.5, 4≤e≤12, and 0<f≤10:    -   Li_(g)As_(h)Sn_(j)S_(k)O_(l), wherein 2≤g≤6, 0≤h≤1, 0≤j≤1,        2≤k≤6, and 0≤l≤10;    -   Li_(m)P_(n)S_(p)I_(q), wherein 2≤m≤6, 0 ≤n≤1, 0≤p≤1, 2≤q≤6; or    -   a mixture of (Li₂S):(P₂S₅) having a molar ratio from about 10:1        to about 6:4 and LiI, wherein the ratio of [(Li₂S):(P₂S₅)]: L is        from 95:5 to 50:50;    -   a mixture of LiI and Al₂O₃;    -   Li₃N;    -   LPS+X, wherein X is selected from Cl, I, or Br;    -   vLi₂S+wP₂S₅+yLiX;    -   vLi₂S+wSiS₂+yLiX;    -   vLi₂S+wB₂S₃+yLiX;    -   a mixture of LiBH₄ and LiX wherein Xis selected from Cl, I, or        Br; or    -   vLiBH₄+wLiX+yLiNH₂, wherein X is selected from Cl, I, or Br; and    -   wherein coefficients v, w, and y are rational numbers from 0 to        1.

In some examples, the electrochemical cell herein includes a solidseparator which includes a lithium-stuffed garnet oxide characterized bythe formula Li_(a)La_(v)Zr_(x)O_(y).zTa₂O₅, wherein

-   -   u is a rational number from 4 to 10;    -   v is a rational number from 2 to 4;    -   x is a rational number from 1 to 3;    -   y is a rational number from 10 to 14; and    -   z is a rational number from 0 to 1;    -   wherein u, v, x, y, and z are selected so that the        lithium-stuffed garnet oxide is charge neutral.

In some examples of the above formula, u is selected from 4, 5, 6, 7, 8,9, and 10; v is selected from 2, 3, and 4; x is selected from 1, 2, and3; y is selected from 10, 11, 12, 13, and 14; and z is selected from 0,0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65,0.7, 0.75, 0.8, 0.85, 0.9, 0.95, and 1.

In some examples, the electrochemical cell herein includes a solidseparator which includes a lithium-stuffed garnet oxide characterized bythe formula Li_(a)La_(v)Zr_(x)O_(y).zNb₂O₅, wherein

-   -   u is a rational number from 4 to 10;    -   v is a rational number from 2 to 4;    -   x is a rational number from 1 to 3;    -   y is a rational number from 10 to 14; and    -   z is a rational number from 0 to 1;    -   wherein u, v, x, y, and z are selected so that the        lithium-stuffed garnet oxide is charge neutral.

In some examples of the above formula, u is selected from 4, 5, 6, 7, 8,9, and 10; v is selected from 2, 3, and 4; xis selected from 1, 2, and3; y is selected from 10, 11, 12, 13, and 14; and z is selected from 0,0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65,0.7, 0.75, 0.8, 0.85, 0.9, 0.95, and 1.

In some examples, the electrochemical cell herein include a solidseparator which includes a lithium-stuffed garnet oxide characterized bythe formula Li_(u)La_(v)Zr_(x)O_(y).z Ga₂O₃, wherein

-   -   u is a rational number from 4 to 10;    -   v is a rational number from 2 to 4;    -   x is a rational number from 1 to 3;    -   y is a rational number from 10 to 14; and    -   z is a rational number from 0 to 1;    -   wherein u, v, x, y, and z are selected so that the        lithium-stuffed garnet oxide is charge neutral.

In some examples of the above formula, u is selected from 4, 5, 6, 7, 8,9, and 10; v is selected from 2, 3, and 4; x is selected from 1, 2, and3; y is selected from 10, 11, 12, 13, and 14; and z is selected from 0,0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65,0.7, 0.75, 0.8, 0.85, 0.9, 0.95, and 1.

In some examples, the electrochemical cell herein includes a solidseparator which includes a lithium-stuffed garnet oxide characterized bythe formula Li_(u)La_(v)Zr_(x)O_(y).zTa₂O₅.bAl₂O₃, wherein

-   -   u is a rational number from 4 to 10;    -   v is a rational number from 2 to 4;    -   x is a rational number from 1 to 3;    -   y is a rational number from 10 to 14;    -   z is a rational number from 0 to 1;    -   b is a rational number from 0 to 1; and    -   wherein z+b≤1

In some examples of the above formula, u is selected from 4, 5, 6, 7, 8,9, and 10; v is selected from 2, 3, and 4; xis selected from 1, 2, and3; y is selected from 10, 11, 12, 13, and 14; and z and b are eachindependently selected from 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35,0.4, 0.45, 0.5, 0.55, 0.6 0.65, 0.7 0.75, 0.8, 0.85, 0.9, 0.95, and 1.

In some examples, the electrochemical cell herein includes a solidseparator which includes a lithium-stuffed garnet oxide characterized bythe formula Li_(u)La_(v)Zr_(x)O_(y).zNb₂O₅.bAl₂O₃, wherein

-   -   u is a rational number from 4 to 10;    -   v is a rational number from 2 to 4;    -   x is a rational number from 1 to 3;    -   y is a rational number from 10 to 14;    -   z is a rational number from 0 to 1;    -   b is a rational number from 0 to 1;    -   wherein z+b≤1; and    -   wherein u, v, x, y, and z are selected so that the        lithium-stuffed garnet oxide is charge neutral.

In some examples of the above formula, u is selected from 4, 5, 6, 7, 8,9, and 10; v is selected from 2, 3, and 4; x is selected from 1, 2, and3; y is selected from 10, 11, 12, 13, and 14; and z and b are eachindependently selected from 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35,0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, and 1.

In some examples, the electrochemical cell herein includes a solidseparator which includes a lithium-stuffed garnet oxide characterized bythe formula Li_(u)La_(v)Zr_(x)O_(y).z Ga₂O₃.bAl₂O₃, wherein

-   -   u is a rational number from 4 to 10;    -   v is a rational number from 2 to 4;    -   x is a rational number from 1 to 3;    -   y is a rational number from 10 to 14;    -   z is a rational number from 0 to 1; and    -   b is a rational number from 0 to 1;    -   wherein z+b≤1;    -   wherein u, v, x, y, and z are selected so that the        lithium-stuffed garnet oxide is charge neutral.

in some examples, u is selected from 4, 5, 6, 7, 8, 9, and 10. in someexamples, v is selected from 2, 3, and 4. In some examples, x isselected from 1, 2, and 3. n some examples, y is selected from 10, 11,12, 13, and 14. In some examples, z and b are each independentlyselected from 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5,0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, and 1.

In some examples, the electrochemical cell herein includes a positiveelectrode in direct contact with a solid electrolyte separator.

In some examples, the electrochemical cell herein includes catholytewhich includes an additives such as VC (vinylene carbonate), VEC (vinylethylene carbonate), succinic anhydride, PES (prop-1-ene, 1-3 sultone),tris(trimethylsilyl) phosphite, ethylene sulfate, PBF, TMS(1,3-propylene sulfate), propylene sulfate, MMDS, trimethoxyboroxine,FEC, combinations thereof, and the like.

In some examples, the solid seperater of the electrochemical cell is athin and free standing sintered garnet film, wherein the film thicknessis less than 50 μm and greater than 10 nm, wherein the film comprises agarnet characterized by the formula Li_(x)La₃Zr₂O₁₂.qAl₂O₃, wherein xranges from 5.5 to 9; and q ranges from 0.05 to 1.0; and wherein thefilm is not adhered or fixed to a substrate. In some examples, the molarratio of Al₂O₃:Li_(x)La₃Zr₂O₁₂, is 0.35, 0.5, 0.67 or 1.0. In someexamples, the film has a surface roughness of less than 5 μm. In someexamples, the garnet has a median grain size of between 0.1 μm and 10μm. In some examples, the film has an area specific resistance (ASR) ofless than 10 Ωcm². In some examples, the film has an area specificresistance (ASR) of less than 10 Ωcm² at 80° C. In some examples, thecarbon content is less than 5 atomic %. In some examples, the filmthickness is about 49 μmin some examples, the solid seperator of theelectrochemical cell is a thin film comprising a lithium stuffed garnetand Al₂O₃, wherein the lithium-stuffed garnet is characterized by theempirical formula Li_(x)La_(y)Zr_(z)O_(t), wherein 5.5<x<6.7, 1.5<y<4,1≤z≤2, 10≤t≤13; and wherein the molar ratio of Al₂O₃: garnet is between0.05 to 0.7; wherein the thin film has a film thickness of about 10 nmto about 100 μm; and wherein the thin film has grains having a d₅₀diameter between 100 nm and 10 μm. In some examples, the thin film ischaracterized by the empirical formula Li_(x)La₃Zr₂O₁₂. p1/2Al₂O₃;wherein 5.5<x<6.7 and 0.1<p<1.4. In some examples, the molar ratio ofAl₂O₃:garnet is between 0.25 and 0.45. In some examples, the molar ratioof Al₂O₃: garnet is 0.35. In some examples, the film thickness is lessthan 50 μm and greater than 10 nm. In some examples, the thin film is athin film monolith. In some examples, the thin film is a sintered thinfilm monolith. In some examples, the thin film has a density of about4.5-5.2 g/cm³.

E. METHODS OF MAKING

In some examples, set forth herein is a method for making a catholyteset forth herein which includes a nitrile solvent and a lithium salt,wherein the method includes providing a nitrile solvent, providing alithium salt, mixing the dinitrile solvent and the lithium salt to forma mixture, and optionally heating the mixture. In some examples, thenitrile solvent is a dinitrile solvent. In some examples, the nitrilesolvent comprises or is selected from those solvents described abovewith respect to the catholyte of the present invention(s). In someexamples, the nitrile solvent has the properties described above withrespect to the catholyte of the present invention(s). In some examples,the lithium salt is selected from those lithium salts described abovewith respect to the catholyte of the present invention(s). In someexamples, the nitrile solvent further comprises a solvent selected fromthose described above with respect to the catholyte of the presentinvention(s).

In some examples, set forth herein is a method for making a catholyteset forth herein which includes an organic sulfur-including solvent anda lithium salt, wherein the method includes providing an organicsulfur-including solvent, providing a lithium salt, mixing the organicsulfur-including solvent and the lithium salt to form a mixture, andoptionally heating the mixture. In some examples, the method includesdrying the solvent(s) and/or salts before or after mixing. In someexamples, the drying comprises heating and/or processing the materialwith a dessicating or absorbing material.

F. METHODS OF USING

In some examples, set forth herein is a method of using anelectrochemical cell, which is set forth herein, or using anelectrochemical cell that includes a catholyte, which is set forthherein. In some of these methods, the methods include charging theelectrochemical cell to a voltage greater than 4.3V. In some methods,the methods also include discharging the electrochemical cell to avoltage less than 4.3V.

In some examples, the methods herein include charging the battery to avoltage greater than 4.4V. In some examples, the methods herein includecharging the battery to a voltage greater than 4.5V. In some examples,the methods herein include charging the battery to a voltage greaterthan 4.6V. In some examples, the methods herein include charging thebattery to a voltage greater than 4.7V. In some examples, the methodsherein include charging the battery to a voltage greater than 4.8V. Insome examples, the methods herein include charging the battery to avoltage greater than 4.9V. In some examples, the methods herein includecharging the battery to a voltage greater than 5.0V. In some examples,the methods herein include charging the battery to a voltage greaterthan 5.1V. In some examples, the methods herein include charging thebattery to a voltage greater than 5.2V. In some examples, the methodsherein include charging the battery to a voltage greater than 5.3V. Insome examples, the methods herein include charging the battery to avoltage greater than 5.4V. In some examples, the methods herein includecharging the battery to a voltage greater than 5.5V.

In some examples, the methods herein include charging the battery underpressure. In some examples, the pressure is about 50-300 pounds persquare inch (PSI). In some examples, the pressure is about 50 PSI. Insome examples, the pressure is about 60 PSI. In some examples, thepressure is about 70 PSI. In some examples, the pressure is about 80PSI. In some examples, the pressure is about 90 PSI. In some examples,the pressure is about 100 PSI. In some examples, the pressure is about110 PSI. In some examples, the pressure is about 120 PSI. In someexamples, the pressure is about 130 PSI. In some examples, the pressureis about 140 PSI. In some examples, the pressure is about 150 PSI. Insome examples, the pressure is about 160 PSI. In some examples, thepressure is about 170 PSI. In some examples, the pressure is about 180PSI. In some examples, the pressure is about 190 PSI. In some examples,the pressure is about 200 PSI. In some examples, the pressure is about210 PSI. In some examples, the pressure is about 220 PSI. In someexamples, the pressure is about 230 PSI. In some examples, the pressureis about 240 PSI. In some examples, the pressure is about 250 PSI. Insome examples, the pressure is about 260 PSI. In some examples, thepressure is about 270 PSI. In some examples, the pressure is about 280PSI. In some examples, the pressure is about 290 PSI. In some examples,the pressure is about 300 PSI.

In some examples, the methods herein include discharging the batteryunder pressure. In some examples, the pressure is about 50-300 poundsper square inch (PSI). In some examples, the pressure is about 50 PSI.In some examples, the pressure is about 60 PSI. In some examples, thepressure is about 70 PSI. In some examples, the pressure is about 80PSI. In some examples, the pressure is about 90 PSI. In some examples,the pressure is about 100 PSI. In some examples, the pressure is about110 PSI. In some examples, the pressure is about 120 PSI. In someexamples, the pressure is about 130 PSI. In some examples, the pressureis about 140 PSI. In some examples, the pressure is about 150 PSI. Insome examples, the pressure is about 160 PSI. In some examples, thepressure is about 170 PSI. In some examples, the pressure is about 180PSI. In some examples_(;) the pressure is about 190 PSI. In someexamples, the pressure is about 200 PSI. In some examples, the pressureis about 210 PSI. In some examples, the pressure is about 220 PSI. Insome examples, the pressure is about 230 PSI. In some examples, thepressure is about 240 PSI. In some examples, the pressure is about 250PSI. In some examples, the pressure is about 260 PSI. In some examples,the pressure is about 270 PSI. In some examples_(;) the pressure isabout 280 PSI. In some examples, the pressure is about 290 PSI. In someexamples, the pressure is about 300 PSI.

In some examples, set forth herein method of storing an electrochemicalcell, wherein the methods includes providing an electrochemical cell ofany one of claims, wherein the an electrochemical cell has greater than20% state-of-charge (SOC): and storing the battery for at least one day.

In some examples, the storing the battery is for at least two days.

In some examples, the storing the battery is for at least three days.

In some examples, the storing the battery is for at least four days.

In some examples, the storing the battery is for at least five days.

In some examples, the storing the battery is for at least six days.

In some examples, the storing the battery is for at least seven days.

In some examples, the storing the battery is for at least eight days.

In some examples, the storing the battery is for at least nine days.

in some examples, the storing the battery is for at least ten days.

In some examples, the storing the battery is for at least eleven days.

In some examples, the storing the battery is for at least twelve days.

In some examples, the storing the battery is for at least thirteen days.

In some examples, the storing the battery is for at least fourteen days.

in some examples, the storing the battery is for at least fifteen days.

In some examples, the storing the battery is for at least sixteen days.

In some examples, the storing the battery is for at least seventeendays.

In some examples, the storing the battery is for at least eighteen days.

In some examples, the storing the battery is for at least nineteen days.

In some examples, the storing the battery is for at least twenty days.

In some examples, the storing the battery is for at least twenty-onedays.

In some examples, the storing the battery is for at least twenty-twodays.

In some examples, the storing the battery is for at least twenty-threedays.

in some examples, the storing the battery is for at least twenty-fourdays.

In some examples, the storing the battery is for at least twenty-fivedays.

In some examples, the storing the battery is for at least twenty-sixdays.

In some examples, the storing the battery is for at least twenty-sevendays.[and 28, 29, and 30 days]

In some example, the storing the battery for at least one day is at atemperature greater than 20° C. In some other examples, the storing thebattery for at least one day is at a temperature greater than 40° C.

In any of the methods, above, in some examples, the method furtherincludes charging the battery to a voltage greater than 4.3V v. Li.

G. EXAMPLES

To record conductivity, a Biologic VMP3 was used. An electrochemicalcell was constructed with blocking electrodes. A catholyte material wasmade as a gel and was used to fill the porosity of a porous separatorsuch as a Celgard membrane or glass fiber separator. To record the massfraction of electrolyte, a mass loss on drying tool such as an ArizonaInstruments Computrac Max 5000XL #1 was used. Electrochemical cyclingwas performed with Arbin BT-G or BT-2043.

To record vapor pressure, Micromeritics BET tool was used.

Example 1 ASRdc of Nitrile and Carbonate Cathode Electrolytes

In this Example, the ASRdc increase in electrochemical cells stored at4.6V and 45° C. was monitored for four weeks. Herein, ASRdc is theArea-specific resistance (area specific resistance), which is determinedby measuring the difference in voltage from the end of a 30 minutecurrent pulse to a steady state value after 10 minutes. This means thatASR was determined by measuring a voltage change and calculating ASR bythe equation, ASR=ΔV/j where ΔV is the voltage change after a currentpulse in a GITT (Galvanostatic intermittent titration technique) testand j is the current density applied to the cell in the GITT test.

One electrochemical cell included a cathode, layered with a gelelectrolyte (i.e., catholyte), which was layered with a solid garnetseparator, and to which the opposite side of the solid garnet separatorwas layered with Li metal by evaporation. The cell was maintained at apressure of about 50-300 psi. The gel electrolyte included ethylenecarbonate:ethyl-methyl-carbonate (EC:EMC) in a 3:7 w/w ratio+1M LiPF₆ at2 w/w FEC. The solid garnet separator is a pellet cell which can beprepared according to the methods disclosed in U.S. ProvisionalApplication No. 62/544,724 filed Aug. 11, 2017, which is incorporated byreference herein in its entirety.

A second electrochemical cell included a cathode, layered with aelectrolyte (i.e., catholyte), which was layered with a solid garnetseparator, and to which the opposite side of the solid garnet separatorwas layered with Li metal by evaporation. The cell was maintained at apressure of about 50-300 psi. The electrolyte included succinonitrileand 12 mol % LiBF₄.

The two cells described in this Example were stored at high voltage(4.6V) at 45° C. and monitored for four weeks. After each week, eachcell was discharged to measure the self-discharge, followed by a fullcharge-discharge at C/10, 2.7-4.5V, with 30 min pulses followed by 1 minrests to measure the ASR.

From this data, the ASR was calculated and the results are presented inFIGS. 2 and 3. Median charge and discharge ASRdc increased each week. Itcan be seen that the cell impedance growth was less for the cell withthe nitrile catholyte compared to the cell with the carbonateelectrolyte. The data also indicates that the nitrile catholyte performsbetter at higher voltages and higher state of charge than do carbonatecatholytes, when assembled with a solid-state electrolyte as in thisExample.

Example 2 Stability Tests of Electrochemical Cells Having Nitrile orCarbonate Cathode Electrolytes

This Example compares electrolyte performance when the coin cell cap, onthe anode side, has been compromised. In this example, a hole wasdrilled into the coin cell cap, on the anode side. The cell included acathode, layered with a electrolyte (i.e., catholyte), which was layeredwith a solid garnet separator, and to which the opposite side of thesolid garnet separator was layered with Li metal by evaporation. Thecell was maintained at a pressure of about 50-300psi. The electrolyteincluded ethylene carbonate:ethyl-methyl-carbonate (EC:EMC) in a 3:7 w/wratio+1M LiPF₆ at 2 w/w FEC.

In a second cell, the cell included a cathode, layered with aelectrolyte (i.e., catholyte),which was layered with a solid garnetseparator, and to which the opposite side of the solid garnet separatorwas layered with Li metal by evaporation. The cell was maintained at apressure of about 50-300psi. The electrolyte included succinonitrile and12 mol % LiBF₄.

Both of the two cell batches in this Example were tested in a gloveboxat 45° C. within an hour of the crimping. 1/16 inch holes werepre-drilled in the anode cap, which was then used in a standard cellbuild. Within an hour after crimping, the cells were put on test in aargon-filled glove box at 45° C. The test included a GITTcharge-discharge protocol of a pulsed C/10 charge followed by a pulsedC/3 discharge.

The results are presented in FIG. 4. The cell with the nitrileelectrolyte maintained a substantial fraction of its capability todischarge energy, while the cell with the carbonate electrolyte did notmaintain a substantial fraction of its capability to discharge energy.

Example 3 Stability Tests of Electrochemical Cells Having Nitrile orCarbonate Cathode Electrolytes

This Example compares the storage stability of two types ofelectrochemical cells. One electrochemical cell included a cathode,layered with a gel electrolyte (i.e., catholyte), which was layered witha solid garnet separator, and to which the opposite side of the solidgarnet separator was layered with Li metal by evaporation. The cell wasmaintained at a pressure of about 50-300 psi. The cell included a sealaround the garnet to isolate the cathode/catholyte from the lithiumanode. The gel electrolyte included ethylenecarbonate:ethyl-methyl-carbonate (EC:EMC) in a 3:7 w/w ratio+1M LiPF₆ at2 w/w FEC.

A second electrochemical cell included a cathode, layered with aelectrolyte (i.e., catholyte),which was layered with a solid garnetseparator, and to which the opposite side of the solid garnet separatorwas layered with Li metal by evaporation. The cell was maintained at apressure of about 50-300psi. The electrolyte included succinonitrile and12 mol % LiBF₄.

Both of the two cells were monitored for impedance growth duringcycling. The electrochemical cell having the succinonitrile solvent inthe cathode electrolyte was observed to have a lower impedance growth,over 50 cycles, when compared to the electrochemical cell having thecarbonate solvent in the cathode electrolyte. The electrochemical cellhaving the succinonitrile solvent therefore had a greater power andenergy capability than the electrochemical cell having the carbonatesolvent in the cathode electrolyte.

The results are presented in FIG. 5.

Example 4 Stability Tests of Electrochemical Cells Having Nitrile orCarbonate Cathode Electrolytes

In this example, two PVDF-HFP gel polymer films were soaked inadiponitrile or EC:EMC. While the gel films were held at 45° C., thefilms were monitored for mass loss over time in an open system. Over twohours, the EC:EMC evaporated quickly and significantly, whereas theadiponitrile was stable and did not evaporate quickly or significantly.This shows that the nitrile catholyte is more stable within the cathodeat elevated temperature than is the carbonate catholyte. The nitrilecatholyte should therefore be suitable for use in high temperatureoperations.

The results are shown in FIG. 6 and Table 1, below:

TABLE 1 EC:EMC (3:7 vol %) + Adiponitrile + 1M LiPF6 1M LiTFSI % solventloss on drying 57 1

This data shows that the solvent loss on drying is much lower fornitrile solvents than for carbonate solvents

Catholyte volatility is problematic for safety and physical stabilityreasons. The Example herein shows that the selected dinitriles are muchless prone to solvent evaporation as compared to carbonates.

Example 5 Stability Tests of Electrochemical Cells Having SulfolaneCathode Electrolytes

Using the Micromeritics BET tool, open beakers were prepared with thefollowing compostions in Table 2 at 45° C. with the compositions shownin the Table 2, and the vapor pressure was noted. Over two hours, theEC:EMC evaporated quickly and significantly, whereas the sulfolanesystem was stable and did not evaporate quickly or significantly. Thisshows that the sulfur-including catholyte is more physically stablewithin the cathode at elevated temperature than is the carbonate ornitrile catholyte. The sulfur-including catholyte should therefore besuitable for use in high temperature operations.

TABLE 2 LOW VAPOR PRESSURE (MEASURED VALUE) Vapor Pressure at 45° C.Composition (mmHg) Ethylene Carbonate + 0.23 Sulfolane 3:7 v/vGlutaronitrile + 0.68 Succinonitrile 0.57:0.43 mol/mol EC:EMC 3:7 w/w27.2

Example 6 High Voltage Storage at a Minimal Capacity Loss

Full cells were prepared with two different catholytes: in one case,ethylene carbonate with 2M LiPF₆, and in the second case, sulfolane with2M LiPF₆. Each full cell device was stored at 45° C. after charging to4.5V. Each week the device was discharged, and the measured dischargecapacity that remained after the week of high temperature storage iscalled the self-discharged capacity . Then the device was charged anddischarged, and the difference between the original capacity and thenewly measured reversible capacity provided the irreversible capacityloss after high voltage storage. The device was charged to 4.5V andstored for another week before repeating the discharge tests. The cellsretained both self-discharged capacity and reversible capacity for fourweeks of storage at 4.5V.

In this example, cathode is prepared with mass fraction 0.91 NMC, 0.010Ketjenblack EC-600JD, 0.050 Kynar Powerflex LBG PVDF 12C9073, 0.030SuperC65; mixed with NMP (N-mthyl-2-pyrolidone) and degassed, then caston carbon-coated aluminum foil, dried at 120° C. under vacuum, andcalendered. There was no bonding layer. Separator was 120 μm thick.

Example 7 ASR GROWTH FOR A SULFOLANE SYSTEM

As shown in FIG. 7, ASR growth wherein the cell was prepared withsulfolane and ethylene carbonate (3:7 v/v)+2M LiPF₆ was a lot smallerthan a cell prepared with ethyl-methyl carbonate, ethylene carbonate(3:7v/v)+1M LiPF₆. The data was obtained for 10 cycles, C/3 pulses, from2.7-4.2 V at 45° C. The cathode was NMC, and the separator wassolid-state separator material. As shown in FIG. 8, a cell was able tocharge and discharge energy for 500 cycles with minimal gain in ASR.

As shown in these Examples, the electrochemical performance forelectrochemical cells having a nitrile catholyte is surprisinglyimproved when compared to electrochemical cells having a carbonatecatholyte. As shown in these Examples, high temperature physicalstability, high voltage stability, elevated temperature powercapability, and cycle life are much better for electrochemical cellshaving a nitrile catholyte than they are for electrochemical cellshaving a carbonate catholyte.

The embodiments and examples described above are intended to be merelyillustrative and non-limiting. Those skilled in the art will recognizeor will be able to ascertain using no more than routine experimentation,numerous equivalents of specific compounds, materials and procedures.All such equivalents are considered to be within the scope and areencompassed by the appended claims.

1.-194. (canceled)
 195. A catholyte comprising, an organicsulfur-including solvent; and a lithium salt; wherein the organicsulfur-including solvent is selected from ethyl methyl sulfone, dimethylsulfone, sulfolane, allyl methyl sulfone, butadiene sulfone, butylsulfone, methyl methanesulfonate, dimethyl sulfite, and combinationsthereof; wherein the lithium salt is selected from LiPF₆, LiBOB, LiTFSi,LiBF₄, LiClO₄, LiFSI, LiAsF₆, LiI, and a combination thereof; andwherein the catholyte is chemically stable when in contact with a solidseparator.
 196. The catholyte of claim 195, further comprising a solventselected from ethylene carbonate (EC), diethylene carbonate, diethylcarbonate, dimethyl carbonate (DMC), ethyl-methyl carbonate (EMC),tetrahydrofuran (THF), γ-Butyrolactone (GBL), fluoroethylene carbonate(FEC), fluoromethyl ethylene carbonate (FMEC), trifluoroethyl methylcarbonate (F-EMC),1,1,2,2-tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy)propane (F-EPE),fluorinated cyclic carbonate (F-AEC), propylene carbonate (PC),dioxolane, acetonitrile (ACN), succinonitrile, adiponitrile,hexanedinitrile, pentanedinitrile, acetophenone, isophorone,benzonitrile, dimethyl sulfate, dimethyl sulfoxide (DMSO), ethylacetate, methyl butyrate, dimethyl ether (DME), diethyl ether, propylenecarbonate, dioxolane, glutaronitrile, and combinations thereof
 197. Thecatholyte of claim 195, further comprising ethylene carbonate, whereinthe organic sulfur-including solvent is sulfolane, wherein the ethylenecarbonate to sulfolane ratio is 3:7 by volume.
 198. The catholyte ofclaim 195, wherein the lithium salt is selected from LiPF₆, LiBOB,LFTSi, and combinations thereof.
 199. The catholyte of claim 195,wherein the lithium salt is LiPF₆ and is present at a concentration of0.5 M to 2 M.
 200. The catholyte of claim 195, wherein the lithium saltis LiTFSI and is present at a concentration of 0.5 M to 2 M.
 201. Thecatholyte of claims 195, wherein the catholyte has a lithiumtransference number of greater than 0.2.
 202. The catholyte of claim195, wherein the catholyte has a total ionic conductivity of greaterthan 1e-4 S/cm at 25° C.
 203. The catholyte of claim 195, wherein thecatholyte further comprises a carbonate solvent.
 204. The catholyte ofclaim 195, wherein the organic sulfur-including solvent is stable up to4.7 V v. Lithium.
 205. The catholyte of claim 195, wherein the organicsulfur-including solvent is stable down to 1.5 V v. Lithium.
 206. Thecatholyte of claim 195, wherein the organic sulfur-including solvent hasa total ionic conductivity of greater than 1e-4 S/cm at roomtemperature.
 207. The catholyte of claim 195, the lithium salt isselected from LiPF₆, LiBH₄, LiBOB, LiBETI, LiTFSi, LiClO₄, LiFSI,LiAsF₆, LiI, LiBF₄, and combination thereof
 208. The catholyte of claim195, wherein the lithium salt is LiBF4.
 209. The catholyte of claim 195,wherein the lithium salt is present in the organic sulfur-includingsolvent at a concentration of about 5-20 mol %.
 210. The catholyte ofclaim 195, wherein a lithium salt is present in the sulfone solvent at aconcentration of about 12 mol %.
 211. The catholyte of claim 195,wherein the lithium salt is present in the sulfone solvent at aconcentration of about 4-25 mol %.
 212. The catholyte of claim 195,wherein a lithium salt is present in the sulfone solvent at aconcentration of about 0.5-3.5 M.
 213. The catholyte of claim 195,wherein the catholyte comprises LiBF4, LiCF₃SO₃, LiN(CF₃SO₂)₂, or acombination thereof
 214. The catholyte of claim 195, further comprisingLiBF₄ or LiN(CF₃SO₂)₂.
 215. The catholyte of claim 195, furthercomprising an additives selected from VC (vinylene carbonate), VEC(vinyl ethylene carbonate), succinic anhydride, PES (prop-1-ene, 1-3sultone), tris(trimethylsilyl) phosphite, ethylene sulfate, PBF, TMS(1,3-propylene sulfate), propylene sulfate, trimethoxyboroxine, FEC, andcombinations thereof.